@Tanya Maslach most STR and MTR guests book site unseen. 

Its free on our site, but happy to share a link if anyone is interested  Hi Kelly - could you share that tracker with me? 

What’s the minimum we’d need on site to get started with some tent camping sites?

Does that mean you're doing fully self serve showings?

Quote from @Jonathan Greene: Quote from @Russell Brazil: The email and acknowledgement serve as the mutually agreed release in writing.

In fact, given the start up costs, the best way to make a profit as an MTR is to earn the continuing support of the property owner served.  

Go to Etsy and search for "rental property tracker," and you will find hundreds of nice spreadsheets to track 10-20 rentals, usually for under $10.Software has extremely helpful features like online payments, marketing syndication (click a button, and your property is advertised on multiple sites), electronic document review/signing, maintenance tracking, and owner reports.

Interlink these pages within your site where relevant.

My opinion is anyone that has to ask where/how to find off-market (underground) properties is better served by purchasing off the MLS. 

If you can get gross development value then you can figure what the most you can pay to make the site pad ready, do vertical and still make a profit.