@Katelyn Rylee Yea Single family rentals I would say are the safest bet. 

You bet.

I bet you already know enough and know what your options are to get started so go and make it happen!

Research the area, look at reviews, called several property managers, give them some common situations that occur to see how they would handle that personally, made sure they were familiar and had knowledge about the market they are managing in.

Rising oceans are a real concern but I'm betting it takes longer than 3 years for Charleston.   

Review the lease, even if its written as 25%, landlords may provide shady accounting.

What you should be careful is the consistency of your bookkeeping whether you book in accrual basis or cash basis otherwise your accountant will be confused when he or she reviews your book at the end of year at filing your tax return.If you are familiar with accrual basis accounting, maybe it is a good idea to book it accordingly because accrual basis is better to monitor the performance which is profit and loss of your business monthly.

It does have a hold button, but then some reviews said that the hold really didn't work.

I would think that city code enforcement would be the best bet if they are inside of city limits. 

Your best bet on a fix and flip is to use a private money lender or a hard money lender.