A vacant single family teaches you processes: buying an investment property, assessing and performing whatever fixup needs to be done, marketing to get it rented, collecting applications, the legalities of your state's tenant/landlord laws.It's true that when it's vacant, it's 100% vacant, but as you learn how to be a landlord, it won't be vacant often and then it's 100% occupied.

Are all the units even legal?

I'm currently trying to sell it, and some strange issues have come up.The house is a single-family according to the County, but shares a driveway with two townhouses, and the developer set it up as a condominium complex in the legal description. 

Legally how much notice do we need to give them?

One way, is to set bandit signs if they are legal. 

If you ever go to enter your property, emergency or not, and the tenant has changed the lock, you are within your legal right to have a locksmith come and change the lock on YOUR property.

It seems like a headache to update legal documents knowing I’m going to move often using my personal address .

In some states it's also difficult to market your contract legally.

I’m not sure how foreclosures are handled in Florida, but, if a legal notice has to be filed prior to the foreclosure  sale date, that is your lead source.

any ways hes a tax and legal expert no fluff type gives it to you straight check him on YouTube if you haven't heard of him.