Thanks for using justanswer. This is Leela and I will help you with the question today.
First I would like to congratulate on the domain Vegas. Com, if you own it. It is a very valuable domain.
I need few details more details from you so that I can suggest on using sub domain or single site.
Do you expect any one specific service to be used a lot than another service?
The advantage of using sub domain is that you can use dedicated server for any huge demand service in the future, keeping all the other services on a single server.
Please let me know your thoughts.
I understand that you are are looking to use WordPress.
WordPress supports sub domain based multiple sites. So we can have multiple services on multiple sub domains.
I am sorry for the confusion. You have asked for suggestion and i shared my thoughts on using sub domains, etc.
I have been waiting for your questions. Can you please let me know queries you have?
I am sorry i didnt realize you are looking for Addon recommendations. I know few addons, will explore and share the details in sometime.
Based on my experience I have few recommendations.
Please check https://www.checkfront.com/ if you want to show multiple resorts, hotel rooms, availability.
In case you want to have availability and booking for only ONE resort or hotel then you can use WP Booking system http://www.wpbookingsystem.com/
I would recommend you to play around with the DEMO SITES before you buy any plugin.