Depending on your criteria it can be a bit tricky to locate good investments due to the differences street to street being pretty significant in many places.

Very broad answer to your questions I know, but it all depends on what you are trying to accomplish.

You'll pay 75-80% ARv depending on area.

You would be better served to collect quotes from a handful of foundation specialists then choose one.As for costs, it will be dependant on many factors: type of foundation; type of soil/rock; depth of underpinning / ease of soil removal; and your location.

Depending on the town/city and the property use, you might have to have things like certifications for smoke detectors, CO2 detectors, and fire extinguishers.

Depending on the damage, this hurricane will definitely affect real estate prices in South Florida including Miami.

.- future assumptions: 2% annual income growth, 5% PV growth, 2% expenses growth, 6% sale expensesBigger pockets tool sheet with above data:Cash flow: $916/monthCash on Cash ROI: 6.65%-7.57% depending on rehab costsPurchase cap rate: 7.15%I know this does not meet the 2% or 50% rule but it seems like a good investment for the area.  

The lease or lack thereof might not be an issue depending on what the actual issue here is.

California legalized recreational marijuana use can I prohibit it use on the property?

I guess you could talk to the vendor if the property is not close, but depending on how much work the PM is sending them, this may be a dead end.