Im not clear on the laws in Mass but a 6-unit building is generally considered as a commercial-grade investment and will require a deeper level of underwriting (and time to close) by the 75% debt lender. 

Below are some baselines, but you'll want to dig in deeper to the unknowns so you can run your numbers Snow removal: $600-$900Gas & Electric: ask for records on the property in question Transit Occupancy Tax: 10-14% depending on market/jursidiction Management Fees: 8-25% depending on scope of services offeredPermitting: Varies per county, 2 states & 4 counties in the Tahoe BasinSewer & Water:  varies per county, ask for recordsTrash & recycle: varies per county, ask for recordsBear Box installation: If not present, required for most STR homes. $1400-$2500 depending on size.Im sure I am missing some but thats a start!

I have done a quick read through that site, so good to know it's the right place and I'll be digging deeper soon. 

This is a detailed handbook for syndicators.If you decide you want to take a deeper dive in vetting syndicators and fund managers, I recommend @Brian Burke's book The Hands-Off Investor.You should also consider joining a community of syndicators and investors.

Short term rental is an excellent industry to delve into.

Prior to wasting any energy on diving deeper into a market or running the numbers on a property, it is critical that we have a good understanding of the local ordinances/restrictions.

Just ponder on this for a moment and see if it’s “worth it” to dig deeper and get to know your desired market better to compete against the local veterans.Real estate flipping/investing is definitely not easy as it looks. 

I began to understand this on a deeper level.

We're going to take a deeper dive into these notions and explore why cost averaging is the most sensible approach to House Hacking.

Company like propertyiq.com can go slightly deeper by looking from the deeds and mortgage record which you can do manually also if you have time.