How to build a lead capture CRM for your business with v0 (no coding required)

Rule of thumb: if your lead volume moves around, or the four products above are already talking to each other through a fifth, building your own pays for itself inside a year and never charges you by the response again. If you are one person still finding out whether anybody wants the thing, rent it for now and come back when a meter starts deciding your marketing for you.

* Supabase’s free tier is a building tier rather than a running-a-business tier: 500 MB of database, 2 active projects, and a pause after a week without activity. That pause matters more here than on most apps, because the form embedded on your website goes down with the project, and a lead that arrives while nobody was signed in is not queued anywhere. The Pro plan, from $25/mo, keeps it awake.

Both columns end the same way: the code is yours, nothing charges you by the response, and the thousandth lead in a month costs exactly what the first one did. The difference is whose hours go in: a developer’s, invoiced at $13k-$53k, or your own, spent describing the app and checking what comes back.

Prices and rates from supabase.com, developex.com, v0.app, v0.app and vercel.com, checked August 2026.

The database step is the one worth not skipping once your screens need real data. Everything else here takes a couple of minutes, and after that you’re just describing what you want.

1. 01

   Design the form your visitors will actually see

   Start where v0 is strongest and where this product lives or dies. Nothing is saved yet, and that is fine: you are settling what you ask a stranger for.

   PromptDesign the capture formCopy

   Build a lead capture form as a standalone page with no navigation and no app chrome around it, so it can sit inside somebody else’s website later. Fields: name, email, company, phone, and a message. Mark name and email required, validate the email properly, show a clear error under each field, and show a thank-you state after submitting rather than a blank screen. It does not need to save anywhere yet.

   This page is the one a stranger meets. Getting it right before there is a database behind it costs nothing and settles what you are collecting.

2. 02

   Say plainly that it needs a database

   This is the step to be explicit about. v0 treats the backend as its own request rather than assuming it, so name the tables you want and say the form should write to one of them.

   PromptAdd the database behind itCopy

   Connect a Supabase database to this project and create the tables, then make the form from the last step actually write to it. Leads: name, email, company, phone, source (form, chat, import or manual), status (new, contacted, qualified, converted or rejected), a score, and the rep it is assigned to. Forms: title, slug, published flag, and fields as JSON. Submissions: the raw answers, the form they came from, and the lead they created. Activities: a lead, a type and a note. Every table gets a created_at. Show me the schema before you create it.

   Naming the tables in the same message as the connection is what stops you getting a database with one table in it and a form that half writes to it.

3. 03

   Add sign-in and the two roles

   The form is public. Everything else is not. An admin who runs the whole thing and a rep who works their own leads, both in place before any access rule is written.

   PromptAdd logins and the two rolesCopy

   Add Supabase authentication with email and password: sign-up, login, logout, a session that survives a refresh, and a guard that sends signed-out visitors to the login page while leaving the public form page reachable by anyone. Then add two roles, admin and rep, stored in a user_roles table rather than in the user's auth metadata, since users can edit their own metadata and could otherwise promote themselves. Add a SECURITY DEFINER has_role function for the rules in the next step.

   The guard has to let the embedded form through. Say so in the prompt, because a route guard added later is the usual way that page stops working.

4. 04

   Open the public door, and only that door

   The awkward requirement at the heart of this app: a stranger has to write a row and must not read one. It is two separate rules, and the second is the one that protects everything you have collected.

   PromptLock the tables to the two rolesCopy

   Turn on row-level security for leads, forms, submissions and activities. A rep can read, add and edit only the leads assigned to them. An admin, checked with has_role, reaches all of them. Put an explicit check on every insert and update, so no one can file a row under another rep’s name or move an existing lead onto them. Update the API routes so they rely on these rules rather than filtering in the page.

   PromptLet a stranger write one row and read nothingCopy

   Now the public path. Allow an anonymous visitor to insert into submissions and nothing else: no reading, no editing, no deleting, and no anonymous access to leads, activities, form content or users. Create the lead from the submission in a server route rather than from the browser. Then tell me how to check it with no account at all: submitting should succeed, and asking for the leads table should come back empty rather than with an error I could mistake for a network problem.

   Get this backwards and every lead you have collected is readable by anyone who opens the browser tools on your own form.

5. 05

   Turn one form into a form builder, and route what it catches

   You have one form. Now make it many, give each one an address you can paste elsewhere, and decide who owns what comes through.

   PromptBuild the form builder and its embedCopy

   Turn the single form into a builder: a screen where I add fields (text, email, phone, select, checkbox), mark which are required, and publish. Give each form a public address at /embed/forms/:slug rendering only that form, with no navigation, and add an Embed tab showing the iframe snippet to paste onto another site. Submitting writes a submission row and shows the thank-you state from step 01.

   PromptAssign each new lead to a repCopy

   Add a server route that turns a new submission into a lead: map the answers onto the lead fields, set the source, check whether that email is already a lead and attach an activity to the existing one rather than creating a duplicate, then assign it to the next active rep in turn. Make the assignment mode a setting whose options are round-robin and unassigned, and record every assignment as an activity so the history shows who got what and when.

   Building the rule as a setting rather than as code is what lets you move to territory or product routing later without reopening the capture path.

6. 06
   Destination

   Try it as a stranger would

   Open the deployed form in another browser with no session and follow one lead through to a rep. From there, live chat and the campaigns are each their own request, and each of them will need the backend named out loud again.

   PromptWalk it end to end and plan what is nextCopy

   Walk me through testing the whole flow. Signed in as an admin, publish a form. Then open its embed address in a private window with no account and submit it. Confirm the lead appears with the right source, that a rep was assigned, and that the same email submitted twice becomes one lead with two activities rather than two leads. Sign in as that rep and confirm they see only their own leads. Fix what does not hold up, then list what to build next (live chat, campaign sequences, AI enrichment) in priority order, naming for each one whether it needs new tables or new server routes.

Review the access rules (row-level security policies) on every table. For each one, tell me in simple terms who can view, add, edit, and delete records, confirm that people can only reach their own data while the right roles can reach more, and flag anything left open that shouldn’t be.

One rule outranks everything above it: the secret key that bypasses your access rules stays on the server. If it ever turns up in the app, in a repository, or pasted into a support ticket, rotate it in the Supabase dashboard before you do anything else.

Any of them will serve this app, and your AI coding tool can wire up whichever you pick. Two things are worth checking before the price. The licence comes first, because free does not always mean free for business use, and Vercel’s Hobby tier says plainly that it is for personal projects. The second is in the warning below, and it is the one that catches people out.

Do the multiplication before you pick. A four-step sequence sent to a thousand new leads is four thousand messages, which sits inside Resend’s free tier and costs about forty cents on SES, so at that size the price is not what you are choosing between. What you are choosing is who takes the blame when mail stops arriving. Volume changes the answer, and it changes it slowly: at a hundred thousand a month the same four steps cost $10 on SES and about $90 elsewhere.

Add one server-side "ai" function that talks to your AI provider, with the key held in server secrets and never anywhere the browser can reach. Then put an "Enrich" action on the lead view that sends the email domain and any fields we already have, asks for the company name, industry and rough size, writes them onto the lead, and marks personal-email domains as not enrichable rather than guessing. This runs on every new lead, so use the cheapest and fastest model tier.

Add a "Score" action that sends the lead’s fields, its source, and its recent activity to the ai function, asks for a 0-100 score and a one-line reason, stores both on the lead, and colours the badge by band. Sort the leads list by score by default and let a rep override it. Scoring runs on every lead too, so keep it on the same cheap, fast tier as enrichment.

Add a "Draft reply" button on the lead view that sends what the lead submitted, the page or form it came from, and any chat transcript to the ai function, and returns a short editable first email in the rep’s own tone. Show it in a modal with copy and insert actions, and never send it automatically. This is everyday writing, so use a mid-tier model rather than the cheapest or the strongest.

v0 doesn’t ship its own model for these prompts, so you bring an API key for whichever provider you want, and v0 writes the route that calls it. Start with a cheap model while you’re still iterating on the prompt itself, then swap in a stronger one for the version that ships, and keep every AI feature behind that one route so there’s only one key to rotate.