Tenants probably don't want to get their landlord mad at them and they don't know the people walking through.Ask Seller/Landlord if tenant is current on rent and how much they are paying.

Estimating construction and remodeling has been around a long time, people who do this are called estimators.There's books, software and even courses on estimating.

I would look for alternative land options that you could use for RV parking since RV parking at homes is very difficult and people don't use their RVs much, but there are a lot of RVs in Texas.

Wasn't sure what to expect posting this thread and real glad to see people dropping their input. 

In high season, I can rent each almost as much as a 4 bedroom house does but off season I do much better as people coming down would prefer a small condo on the beach.  

you either need to connect with a seller directly, or find a wholesaler with one to wholesale. 

If you just put it on Zillow and list it as a furnished rental and then just write that you are open to different lease options, a lot of people should reach out to you.

I love listening to people's stories to learn and be inspired but first here's mine. 

Hey Ingrid, I use gas grills and I have a propane tank connected to the grill and I have a spare just in case.

In general people want their feelings stoked and entertainment.