Jumping into the world of small business is an exciting step, congrats! While not being an app developer myself, I have built a small business and have had to find solutions for similar needs.

There are many efficient off-the-shelve software available in the market today that could address your needs, thus perhaps cutting down the cost and effort involved in developing an app from scratch. You’ve got your Squares, Quickbooks, and other service providers that blend the line of scheduling and invoicing/payment collection.

However, if you’ve considered all these possibilities and still prefer a custom-made app, it always helps to find a local company or even a talented freelancer who can work on your project. This will allow you to have personalized service and to handle any particular details that may be unique to your business.

Reaching out to your local network or even putting out a request on platforms like Upwork could prove fruitful. Always remember to check out their portfolios and examine their previous work closely to see if they align with your vision.

Good luck with your venture! You’re in it for an exciting ride.

Have you checked Calendly? I’ve been using Calendly for scheduling for a while and it’s awesome.

Plus calendly also has this feature where you can charge someone for scheduling a meeting. Though you might need to get a paid subscription for it.

If you really need a custom solution, Stripe and Google Calendar API can do the work for you (or you can also use Calendly API and Stripe). Totally depends on the overall idea you wanna build.

Happy to help if needed. Feel free to drop me a message. I own a development firm and we built Web Apps, Mobile Apps & SaaS products for clients