However, we had 30 day minimums and did lease agreements, as well as guaranteed tenants so it was a much different model.

And raising the rent each year on the same leaseholder is motivation for them to move out when the lease is up!  

We normally get it as a credit, unless it’s held by a 3rd party(pm).You can consult the lease agreement for each tenant, if the LL says someone only paid some or non, you need to get estoppel forms signed by both the LL and tenant, or just risk owning the tenant money they never really paid the LL.

It also keeps track of all tenants applications, lease agreements, maintenance requests, etc

I am still heavily involved in building/yard maintenance and turnover work,  but I leave all the stuff with legal risk (advertising, showing, leasing, enforcement, rent collection, deposits, etc)  to the PM.  

Sometimes they can make the property negative cash flow or in a worse case scenario prevent you from even leasing the place to anyone but family members.

If you are looking at a small multi-family of four units or less:Rent RollReview all leases, addendums, or other agreementsTenant payment historyAny violation notices, delinquenciesList of all maintenance in the past yearSchedule of capital improvements in the past 3-5 yearsUtility bill reviewP&L for current year plus the last 1-2Service contracts (landscaping, cleaning, snow removal, etc.)Inventory of all property owned by SellerThere may be more but this is a good start.

Do a search for Subject To, Wraps, Lease Options, Owner Financing, Land Contract.

Look into master lease agreements.

How many evictions have they handled at the property (may speak to tenant selection quality), how many tenants have left mid-lease (also may speak to the quality of the management, bad managers lose good tenants)?