Duplexes are a little easier than 3-4 units with FHA since they don't have to meet self-sufficiency requirements.

Yes two of the three are mid term and one is long term.

We have had no trouble getting our rents increased as long as we have three comps to support it and send in our request in a timely manner, 60 days out. 

Anything that has a contingency is not cash.Listings here will say cash, hard money, or 203k only if they want all three.

Most of the time, we resolve the situation in less than three months through cash-for-keys agreements, court mediation, or by creating enough pressure that the tenants decide to leave on thier own.We currently manage over 700+ units and flip about 20 multifamily properties a year, the majority of which have inherited tenant problems.

Unit 4 - short-term rental (this would be best for a unit with a separate entrance so you reduce the bother to other tenants because the changeovers will be more here)Is anyone doing all three (LTR, MTR, STR) in their multi or house hack now?

I bought a business where the prior owner had it in an S-Corp, the S-Corp and he was sued personally for three million.

Unless you have millions in cash a rookie RE investor in Boston might have one or two or three properties vs hundreds.

Now, use your job income to pay off the HELOC over three years ($90K plus interest).

Try interviewing at least three managers.1.