Standard policies generally do not cover vacant properties under rehab.

To give a back story, I discovered real estate at about this time last year and have been obsessed ever since.

I don't want to purchase another investment property, and then discover that I don't qualify for a loan on a new primary residence due to DTI being too high.

We made numerous mistakes but the property still has about a $400 a month cash-flow.Since I discovered Bigger Pockets, I'm absolutely obsessed with real estate investing. 

I know in places like Florida that tile is the standard because it is a warm wet climate with no basements.

Greg, your are correct in that the carrier may likely consider this to be an issue of normal wear and tear, and decline the claim since wear and tear is a standard exclusion under most policies. 

If not, what are general standards to use?

You would certainly want protection for yourself if you are hurt and out of pocket for a number of weeks or months, but not sure what options you have outside of the standard health/medical insurance for yourself.  

Only possible snag is if the property you're considering doesn't meet conventional loan standards/requirements.

I think you're right to worry about the 1 bathroom. 2 room rentals per bathroom seems to be a pretty standard setup for many by the room rentals.