It is actually my first rental property and have no prior experience with lease agreements.

This is common for folks at a certain point whether or not they were real estate investors prior to that. 

Yes if your attorney has some experience with RE contracts, that should be good enough.A Real Estate agent can help with comparative market analysis to help you confirm you are getting a good deal.

What are your thoughts on using cap rate vs. comparable sales?

The best suggestion I have is to spend some time comparing your units to the others in your immediate area and don't over-improve as often there is a natural price "cap" in the neighborhood and regardless of the small upgrades that really do improve the living experience, it's hard to make them into the rental rate if you are near the top of your market.

Q&A On Tenant Screening:For Tenant, prior to scheduled showing: 1.What is your preferred move in date?

It is my understanding that financing with a bank mortgage in 1st position and a seller carry back in 2nd position is something that was allowed prior to 2008 but has since died out.

For instance you're just comparing the mortgage (including taxes and insurance hopefully) to your expected rent, but what about repairs?

Tourism is an historic well established business there and make a comparison Mexico Vs Colombia is like compare a tropical island vs a desert .

I include in the depart instructions to have the used linens washed and at least put in the dryer prior to departure.