Fintech · Stripe Connect Marketplace

Owner-Financed Payment Platform — a Stripe Connect marketplace for installment deals

A Stripe Connect marketplace on Bubble.io for payment-first, owner-financed deal management — ACH checkout, KYC onboarding, automated amortization scheduling, seller and buyer dashboards, and a full audit and export layer.

5 Milestones

SCOPE
 

7 Weeks

Timeline

Stripe Connect

Payments

Sellers managing land contracts, vehicle financing, and equipment installment sales operated across spreadsheets, manual bank transfers, and disconnected ledgers. We built a true SaaS marketplace — Stripe Connect for direct seller payouts, ACH prioritization for capped fees, backend amortization math, and row-level privacy so no seller or buyer ever sees another’s ledger.

Key Results Achieved

Payment-first, accurate at scale

Onboard buyers, process ACH directly to the bank, auto-generate amortization, and export tax ledgers — in one platform.

$5

Capped ACH processing fee per transaction, regardless of deal size

500+

Active deals with paginated, fast dashboard performance

7 wk

Design to production handover

The approach

Challenge & solution

The challenge

These are high-dollar, multi-year transactions where accuracy is non-negotiable — a miscalculated amortization schedule or missed late-fee flag has real financial and legal consequences. Existing generic tools offered no structured deal lifecycle, no role-based data isolation, and no compliance layer.

Business challenges
Give sellers one place to onboard buyers and process payments
Guarantee amortization accuracy on high-value, multi-year deals
Cap processing fees so margins survive at any deal size
Isolate every seller's and buyer's financial data
Technical challenges
Route buyer payments directly to seller banks via Stripe Connect
Run amortization math accurately and efficiently at scale
Enforce row-level privacy across sellers and buyers
Keep dashboards fast across 500+ active deals

Our solution

Heavy math — amortization, interest/principal splits, running balances — lives in scheduled backend workflows, never in page-load conditions. Stripe Connect Express handles onboarding and routes payments directly to sellers; ACH Direct Debit is enforced to cap fees.

Core features delivered

Seller dashboard

A multi-deal portfolio overview with search, filtering, and analytics cards — interest YTD, portfolio totals, % of deals current, average days late — built to scan fast across 500+ deals.

Buyer read-only view

A restricted, scoped portal showing only the buyer’s deal parameters, upcoming due dates, and payment history.

Deal creation + amortization

A multi-step flow captures principal, rate, term, start date, and frequency; the schedule renders with principal/interest splits and running balances per row.

ACH checkout

Checkout defaults heavily to ACH Direct Debit and surfaces the fee cap prominently; card options are available but de-prioritized.

Clickwrap legal gate

A mandatory ‘I Accept’ checkpoint blocks dashboard entry and logs the exact agreement text with a timestamp in the audit trail.

Billing + subscription UI

Active cost transparency — current tier, active deal count, live monthly cost, and a dynamic monthly-vs-annual savings alert.

Under the hood

Architecture & technical build

WU-efficient by design. Satellite data types handle ledger rows so the parent Deal record stays light; search uses :first item and :count with constraints instead of :filtered, with pagination past 25 rows. Stripe Connect Express routes funds directly to sellers — Velcod never touches the money.

Architecture overview

Amortization math in scheduled backend workflows, never on page load
Satellite data types for ledger rows keep parent records fast
Row-level privacy rules isolate every seller and buyer
Paginated dashboards sustain 500+ active deals

Key technical components

Backend amortization engine

Auto-generates accurate monthly breakdowns on deal creation and adjusts on every completed or edited transaction.

Stripe Connect Express

Handles KYC/KYB onboarding and routes buyer payments directly to seller bank accounts.

ACH Direct Debit

Enforced at checkout to cap processing fees per transaction regardless of deal size.

Reporting & export layer

PDF statements per deal, year-end CSV ledger exports, contract/receipt uploads, and a comprehensive audit log.

Tech stack

Outcomes

Results & impact

Early outcomes

Sellers onboard buyers, process ACH to their bank, and track schedules in one platform
Late payments flagged and year-end tax ledgers exported
Manual spreadsheets and reconciliation replaced entirely

Business impact

Amortization auto-generates accurate breakdowns and adjusts on every transaction
Every financial action logged in a tamper-evident audit trail
A legally defensible transaction record for sellers and buyers
Our Work

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The last step

Building a payments-first financial platform?

We build Stripe Connect marketplaces with accurate backend financial logic, fee-capped ACH, and audit-grade compliance — engineered to stay fast at scale.

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