How long did it take until your first paid customer?

Will let you know in a few months ;)

No personal experience, since I am not involved in sales. I think that with a good product, this should happen in the first week of work.

I got the first payment from the customer only 2 weeks after launching 😊. It's only a top-up amount of $10 SMS credit as my app's come up with a totally free plan.

It took a lot of time. I was trying to be nice and even attended some special courses online at https://lectera.com/en where are a lot of special ways to learn more about business. Such a way is a really effective option if you want to be connected to main changes and features to make your business interesting to other customers.