I'd do what you can to keep yourself uninvolved with it....but still help your Grandma of course..A trip to the City (Planning/Zoning/Building Depts) will give you some valuable info.

Should We:Sell, take advantage of the capital gains law, move, and pay the mortgage off on the new house, credit cards, etc…?

Of course, live wherever you want, if you see that storms are becoming difficult, it is easier to sell one home and move.

So, you can do a land contract for 12 months, which should allow lender to credit you full value of the land vs the purchase price, but the loan will pay off the land contract, so the lender maintains first lien position.Can't help you with the rest of your question, but you should be able to search for "CPA" here on BP to find experts to reach out to.

Far more than most real estate acitivies and much quicker think about it.. you sell the same info over and over and get paid instantly you have no roofs to fix no tenants to manage etc etc.. you do have reputation management of course.

(Of course, you are less likely to own the building then.) 

Did you finance this deal with a local bank or credit union?

On the flip side, if you've got a bunch of Section 8 tenants living in a building that's in a neighborhood where a lot of the tenant base has good jobs, high credit scores, and are generally reliable people, you've got the most risky tenants in that tenant base and that ain't what ya want.

Since I'm a new immigrant with no credit score, a DSCR with 30-35% down payment is my only option, so the 50K need to include that down payment alongside all other costs (closing, rehab, etc). 

Of course.