A few years ago core logic indicated the average rent increase for the year in this city for a SFH was $600/month.  

When you compare to cities you know think of Detroit as the old urban core.

Whenever you are buying a property out of state you should do a few things to ensure it's as smooth as possible.Don't buy in the roughest neighborhood in the urban core.

Don't buy in the roughest neighborhood in the urban core.

From there you can build your CORE 4 wherever you want to invest in.

I’m making a few assumptions: 1) at least some buyers and sellers will accept much less agent handholding than commonly assumed, 2) the primary value that agents add is a) pricing guidance and b) advising clients on offers and counter-offers, and 3) there’s no truly compelling reason why North America has the highest average commissions in the rich world.

It was a little wild, but it proved something: if the numbers make sense, investors show up.Now, you’re in London, which has its own flavor, but the core idea isn’t too different.

Its not a core business problem, its a incompetent management problem 

The other thing to consider is the age and if you add a second floor will the entire structure need to be brought up to code for hurricane and wind.I live in a neighborhood where the homes are older (not in florida) and the foundations are hollow core CMU and adding a second floor would not be feasible due to soil bearing.

Look up articles on BP on how to find the "core 4".