Yes sure! I built Releasy https://www.releasyapp.io/ primarily to solve my main problem: having my project’s releases tested, validated and approved by my clients. And be paid consequently. When I realized that this was a common problem among web agencies and freelancers, I made Releasy a SaaS. I’m using now and I added also an integrated issue tracker to improve communication with clients.
If all features are approved, your client will be redirected to a stripe or PayPal payment form