Own products · Multi tenant platform
NexLar
Rental management system with PIX billing, automatic late fees, lease contracts, receipts and a listings page.
- Client
- NexiaLabs' own product for landlords, brokers and small real estate agencies
- Where
- Online, anywhere in Brazil
- Technology
- PHP · MySQL · PDO · JavaScript · CSS · Apache · PIX EMV
- Status
- Live · aluguel.nexialabs.com.br
- Development
- André Gomes · NexiaLabs
In short
NexLar is a rental management web system built by André Gomes of NexiaLabs for landlords, brokers and small real estate agencies across Brazil. It creates each lease's monthly installments, calculates late fees and interest per day overdue, and builds the payment request with a PIX copy and paste code for the updated amount, with no payment gateway. It is written in PHP with MySQL as a multi tenant service with a three day free trial, and runs on Hostinger.
The client
People who live off rent usually track everything in spreadsheets, notebooks and WhatsApp chats. Every month they have to remember who is due, work out the late amount, chase payment, write a receipt and still figure out what each property actually earned. NexLar started as a system for a single property portfolio and, in its fourth version, became a product open to the public. Today any landlord can sign up on the website and start with a three day trial, no credit card required.
The challenge
Billing was the core problem. Late fees and daily interest need a fixed rule, and any mistake turns into an argument with the tenant. Bank slips and payment gateways charge a fee on every rent payment, which hurts owners with only a few properties. Each landlord must see only their own data, in a shared system that is cheap to run. And an amount typed in Brazilian format, with dots for thousands and a comma for decimals, could never turn into a different number in the database.
What was built
André wrote NexLar in plain PHP with MySQL so it runs on shared hosting with no extra server cost. Installments are created from the lease, and a daily routine flags overdue ones and generates the next ones. The PIX code is built inside the system, following the Central Bank EMV standard, with the landlord's key and the amount already including fees, so the money goes straight to the owner's account. The payment message comes out ready for WhatsApp from a template the landlord can edit. Each account also gets a public page listing available properties at its own address.
What the system does
- Monthly installments generated automatically from the lease, with a daily routine that flags late payments.
- Flat late fee plus interest prorated per day overdue, with rates configurable per account.
- PIX copy and paste code for the updated amount, with no gateway and no intermediary fee.
- Payment reminder ready to send on WhatsApp, built from an editable template.
- Printable lease contract with annual adjustment alerts based on IGPM, IPCA or INPC.
- Rent receipt ready to print or save as PDF, with fees itemized.
- Cash flow for the last twelve months, expenses and overdue rent per property.
- Public page for each account, with photos, filters and a WhatsApp button to promote the properties.
// For whoever reviews the code: architecture and decisions.
Under the hood
NexLar is a framework free PHP application that talks to MySQL through PDO with prepared statements, served by Apache on Hostinger. Tenant isolation is done by column: properties, tenants, leases, expenses and settings all carry the account ID, set by the session in the dashboard or by the address on the public page. A daily routine file, run from the command line or by an external scheduler with a key, updates installments, emails accounts whose trial is ending and sends the administrator a summary of accounts waiting for activation. Each account's public page uses an Apache rewrite rule that turns a short address into a parameter. The database evolves through numbered SQL migrations, from version two to version five.
Technical decisions
- PIX generated in code, following the EMV standard with a CRC16 checksum, instead of a gateway: the landlord gets paid directly and pays no fee per charge.
- Multi tenancy through an account column in a single database, not one database per client, which keeps it viable on shared hosting and keeps migrations simple.
- Parsing of Brazilian formatted amounts centralized in a single function, after an older parser turned 1200.00 into 120000.
- A cap of three sign ups per IP every 24 hours and an audit log of admin actions, to prevent abuse of the free trial.
Does your business look like this one?
It fits anyone who rents out houses, apartments or offices and wants to stop tracking rent in a notebook, from owners with a few properties to small agencies.
Frequently asked questions
Who developed NexLar?
NexLar was developed by André Gomes Andrade, a full stack developer from Carlos Chagas, Minas Gerais, Brazil, at NexiaLabs, from planning to launch.
Where is the client of NexLar based?
NexiaLabs' own product for landlords, brokers and small real estate agencies. Online, anywhere in Brazil.
Which technologies were used to build NexLar?
NexLar uses PHP, MySQL, PDO, JavaScript, CSS, Apache, and PIX EMV.
Can you build a similar project for my business?
Yes. Every project is custom built, with code and accounts in the client's name. The first step is a WhatsApp conversation at +55 (33) 98465 6356 to understand what you need.
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