My bet is you do not get sued.  

I bet you could make little to no money in 20 hours a week.

Sometimes it's ambiguous, but even then, why should I bother with the company that has numerous unresolved lawsuits, versus another company that is virtually the same but has none.

Best bet is to carefully analyze the zoning maps and regulations or just call the town and ask.

Focus on price versus competition and your weekly and monthly discounts.

I bet you were floored when the person ordered every package you had to offer!!

When you have a duplex and tenants on both sides stay for ten years, it almost guarantees that something isn't right.I would study your market and determine the value of your rental, because I bet you are losing money every month.

Put together a spreadsheet and compare the performance of the subject property if you keep renting it as is for the next 10 or 20 years versus if you rehab and refinance.

I have been playing the multifamily game for almost 10 years now, and the GRM is one of my least favorite methods personally since it ignores so many important factors (steam boiler versus electric baseboard heat as an example). 

If you're looking for the cheapest route, conventional may be a better bet.