Hi @ReneRobles !I wasn’t planning to reply since your message is 2 yearsold 
…but someone just bumped it up, so I figured I might as well answer in case it helps others in the community too!
What you’re describing is totally possible with my app, Cowlendar Booking App
You can let customers pick their stay directly on a calendar, apply different prices depending on the day of the week (e.g., higher rates on weekends), and even adjust the final price based on the number of guests (2 or 3 people, for example).
Payment is handled right after the booking (by Shopify), so it’s a complete flow.
If you want some real-life inspiration, here are a few hotels currently using Cowlendar (if you read that in another 2 years, those links might not be valid anymore haha), you can check how they’ve set it up and maybe get some design ideas too:
https://ambersalacati.com/products/hotelzimmer-1
https://anafrankboutiquehotel.com/products/queen-suite
Let me know if you have any questions!