Most Flutter tutorials show you how to build a todo app. This is not that.
I spent months building Valúa — a real Flutter app currently live on Google Play in Mexico, with paying customers, Firebase Auth, Firestore, and MercadoPago payments fully integrated. Then I packaged the entire foundation into a starter kit so other devs don't have to start from scratch.
Here's what I built, how it works, and why MercadoPago integration is harder than anyone tells you.
The stack

Flutter (Dart) — cross-platform mobile
Firebase Auth — email/password + Google Sign-In
Firestore — real-time database, user data persistence
MercadoPago — payment processing for LATAM (Mexico, Argentina, Brazil, Colombia)

Why MercadoPago and not Stripe?
If you're building for Latin America, this question answers itself. MercadoPago has 50M+ active users in LATAM, local payment methods (OXXO, bank transfer, credit/debit cards), and better conversion rates for Mexican and Argentine users than any international processor.
Stripe works great for USD. MercadoPago works for where your users actually are.
The problem? The Flutter + MercadoPago integration docs are scattered, incomplete, and half of them are outdated. I burned a lot of hours figuring it out. That's exactly what this starter kit solves.
What's inside
The kit includes complete Firebase Auth with email and Google Sign-In already configured, Firestore CRUD operations ready to use, MercadoPago Checkout Pro integration with deep link callbacks, and a clean folder structure ready to extend.
The part nobody tells you about is the deep links for payment callbacks. When MercadoPago redirects back to your app after payment, you need to handle it properly — miss this and your users complete payment but your app has no idea it happened. The starter kit has this already set up and working.
Who this is for

Flutter devs building for the Latin American market
Developers who want Firebase Auth + payments without setting it up from scratch
Anyone tired of integrating MercadoPago with incomplete docs

Get it
This is not a tutorial project. It's extracted from a real app with real paying users in production.
👉 Get the starter kit on Gumroad — $29 USD
If you want something fully custom built, reach out: buildlabig@gmail.com