I am understanding it as subtracting that from the amount I would normally give them? 

Normally the opposite is true i.e. rates down/asset prices up.

Our lender says that's normal because its a vacation home. 

I initially wanted to do a BRRR but since I'm not the from the area, real estate agents are telling me I should maybe start out with a turnkey to get my foot in the door?

Lots of ways to start, but I normally recommend figuring out your WHY, and then match that WHY/your goal, with a location.

I normally suggest being right smack dab in the middle with a low risk B class asset.   

Most MTRs can be anywhere from 1.5-3x the normal LTR rent.

I recently placed in a class a unit (almost $2k/ft value) because it is beach unit and expect higher water contact (normally class a gets real wood).Carpet in common areas in short run is cheap but long run will cost more than concrete stain or LVF.  

I am looking to come in on the 4th though so I can do some scuba diving and site seeing as this will be my 1st time in Cancun.If interested in room hacking and we seem to get off on the right foot, I can look into converting it to a two bed room.I am an IT Manager for the day to day. 

Having two open loans for the property is not ideal as that's double closing costs but maybe that is a fairly normal strategy?