Freelance Marketplace Payment Gateway Integration

My custom-built freelance marketplace is almost ready for launch, and the last critical piece is a rock–solid payment system. I need PayPal, Stripe, and Razorpay fully integrated from deposit to payout, with a true escrow flow that keeps client funds secure until work is approved.

Here is what has to happen:

• Payment gateway integration: connect PayPal REST, Stripe Connect, and Razorpay APIs so clients can fund projects in their preferred currency and freelancers can withdraw without friction.
• API & escrow setup: create the escrow wallet, hold funds, trigger partial or full releases, and handle automatic refunds when milestones are cancelled.
• Secure transaction management: implement webhooks, signature verification, PCI-compliant tokenisation, and clear audit logs to spot or prevent fraud.

The codebase is entirely custom, so the solution must slot cleanly into the existing architecture (PHP/Laravel on the backend, Vue on the front). Clean, well-commented code plus a short hand-over document are essential; a recorded walk-through is a bonus.

Acceptance criteria:
1. Deposits, holds, releases, and payouts succeed in live mode on all three gateways.
2. Webhooks update order status in real time with no race conditions.
3. All sensitive keys stay in environment variables, never the repo.
4. Unit tests cover the main payment scenarios.

Please include a brief portfolio or links to previous marketplace or multi-vendor payment builds so I can gauge fit quickly.