Just so happened to ran into the maintenance guy when I was checking out the property and he let me do a walk through in one of the units being cleaned.

As of the past year or so the “mom and pop” group has posted a lot of maintenance and repair issues (properties are not old as I’ve rehabbed every unit).

It may not come to that, but since this is your first property I would suggest you go through an attorney anyway, even if it's month to month and it just comes down to sending the notice of termination.When I take over a building I also send or deliver a standard "takeover" or "welcome" letter to introduce myself as property manager and let the tenants know the answers to their two main questions: 1) who do I call/contact when I have a maintenance/repair request, and 2) how/where do I pay rent.Then (if the letters were mailed or delivered without meeting the tenants), I follow it up with an in-person meeting to introduce myself and answer any questions they may have.Usually the main question they have, whether they ask it or not, is whether I plan to raise the rent.

Operating expenses including vacancy, maintenance, property management, insurance, taxes shouldn't be more than $200/month.

I was thinking to buy a nice book with tips for home maintenance or something related to that, but I don't want them to think I'm pushing them to do maintenance that I should be doing.  

What do I have to do to collect rents and pay for maintenance for properties he owns?

You will also want to understand common area maintenance, especially if you are targeting 3 units or more (lawn care, snow removal, cleaning and upkeep of common areas, etc) and understand the parking situation.

The property is in Halethorpe (Catonsville, Arbutus) and I just need a general overall maintenance but possibly duct cleaning.

You should also figure out what you want your maintenance call process to look like.

I haven’t ever paid myself anything as I was always trying to put away for any expenses, maintenance etc. as well as trying to pay down the mortgage as quickly as I could on the mortgages too.