A lot of OM's will list the mil rate for the county/property and you can usually back into the property tax amount when you go to the counties website and pull the current tax statement.

The free option is just pick up the phone and call 3 or 4 commercial MF brokers from the bigger shops, say you’re an investor and ask for some comps / old OMs, which will have rent analysis.

Theres also typically a lot of expenses missing from the small multifamily OM you gotta really dig through with someone who owns them locally. 

You get to see OM's, the reporting, be on investor calls, etc.

Currently a 3rd party reads electric meters, prepares a statement for each tenants, mails statements to onsite manager, OM gives tenants statements, tenants pay OM by money order and old owner picks up funds on the 8th of each month.  

I would also suggest starting with the youngest looking person listed in the OM.

I entered my email/phone on the listing brokerage website to get access to the offering memorandum (OM) but otherwise have never spoken with or corresponded with the Seller's agent.

The easiest thing to do is use the info from the property OM and add your business plan for the property and company info. 

Here's the picture of a sample unit the broker used in his OM:

However it was after the OM was published by the broker.