But you're right, the risk of unforeseen issues eating up that profit is way too high to stomach.

Gas, water, electric, 10-15% increase in the scope of work for unforeseen circumstances, grass cutting, etc.

Otherwise like Chris mentioned look at doing the 1st for just a bit more than what you were planning to finance if you had already sold your existing home (do it for a bit more than expected for any unforeseen shortage when you sell, like seller paid borrower concessions, repairs you didn't expect, ect) then get a 2nd mortgage to finance the difference to avoid the PMI and pay off the 2nd when home sells, might want to consider a HELOC on the new property so that once paid off, you still have access to the funds if ever needed and while not needed you don't pay any interest.  

The reality is that vacancies, unforeseen economic conditions, repairs can easily force one to become a motivated seller. 

I would be able repeat this process yearly barring any unforeseen expenses.I have a good friend (I've known him since we were kids and he is also my wife's Cousin) whom does not own property currently, he rents an apartment.  

Another note: Don't forget that life happens - unforeseen events or love interests etc and then others or yourself want out of deals etc.

I understand the liability of the common areas and know there needs to be insurance in place, but are there any other unforeseen issues any of you know about?

The important thing to consider is making sure you have access to funds incase you run into unforeseen issues with the project!

In my opinion, nobody in government (or anywhere else) is smart enough to anticipate the unforeseen consequences of there "mandates"So here is what is going on now.A new proposed ordinance will is going toPut the burden of certifying that rental properties are "lead-safe"Double the cost of the annual rental registration from $35 per unit to $70 per unitRequire landlords to put the lead status of the property into a searchable data base.All tenants to terminate leases and/or suspend some or all rent payments if the property has lead hazards.Fines for landlords who do not show their property to be lead-safe.According to today's Plain Dealer article; the city has inspected 10,000 properties in 2018; and found 10% to have lead violations.

If we sit on the market too long or other unforeseen problems show up in an inspection, we still may go the rental route rather than take less than what we think it’s worth.