mailing to pre foreclosures is pretty low return or odds. 

There is an odd thing about listing STR's (I just listed another one) in that it takes a while to rent consistently. 

@Robert Morrissey, This is an odd question, and I am not sure at what you're actually trying to get at.

It's really a shame because the code where I own my investment property does not have an owner-occupancy restriction to permit an ADU--as it should be if a town wants to increase the supply of housing!

Also as David said watch out for AirBNB restrictions in some of the metro neighborhoods.

Review title commitment and survey to make sure to deed restriction and/or HOA in place that would stop you from doing 4 plex2) Meet up with City/County planning office to make sure 4 plex can be build and lot has enough parking spot . 3) Talk to an architect to get an initial foot print, layout and foundation type (i.e. pier beam or post tension slab) 4) Bid out to get estimate for both soft cost (survey + construction drawings + Permit) and hard cost (cost of building)  Without #3 you really cant get hard estimate Problem is that you may not enough time to hash out #2-4.. prior to closing the land .. 

Make sure the HOA doesn't have restrictions on vacation rentals. 30% is industry standard in most places.

I think its safe to suggest that many authorities from the DEA to local sheriffs are at odds at enforcing the changing laws as they balance the high costs to enforce it.Speaking of Trump...

The pilings are odd though, unless near the intracoastal.  

I'd say about 60% of the time FHA will not work for someone that already owns real estate, but you haven't thus far identified anything that would put you in that 60%, and in fact with that explanation for motivation you just gave I'd say you're odds of "true denial" (instead of "loan originator is misinformed denial") are reduced from about 60% to 40%.