If you can comment how to improve, I might be able to quote a price for you, but for our sake, it should be a complete requirement with all the edge cases, otherwise it has potential for conflict which is unnecessary and can be avoided from the very beginning.
For avoiding booked dates, here is another example,
To normalize expectation, no code cannot compete with tech giants such as Airbnb, it can try to imitate but there will be cases that our users are willing to accept our app because of the content inside, not because our app can be the same as tech giants.