It is recommended to install additional section(s) of 6-mil vapor barrier material OR re-snug/re-set existing material to cover over all exposed soilThere is ACTIVE evidence of more than one kind of wood destroying insect found in the crawl space.

Getting certified in Section 8 and tax credit is another type of class of management that some public housing companies will either want or train employees in.It's a job market that I would say is mid range for pay if within a corporate setting, working for larger company that has maybe over 1500 units and multiple properties where one would be responsible for a smaller complex of maybe 75 to 200 apartments at one site.PM that would work for a PM company might have more commission based earnings. 

If you over pay, you paint yourself into a corner with your possible exit strategies and if your cash flow doesn't work out as expected or something else happens where you need or choose to sell, then you are trapped and the only way to exit is to take a loss and bring money to the closing table.

The mistake you made, as with most hobby landlords, was you fell into the trap of not raising his rent to full market in March of 2017.

What are some things I need to look out for in order to not fall into any traps such as liens on the property etc. ?

Than the real estate agent i was in fell into the same trap of not being optimistic either.

A plumbing modification that requires digging up the curb trap (or something similar) should cost a few grand.

Dude, this one is a trap, i did the due diligence on this because those numbers were so good, property has been on the market for 2 months, gave up on trying to make it work, you are looking at close to 100k rehab costs and even then the building still looks old and unattractive, pm me if you want more info on what i found out.

I immediate suspect sewer gas, may be from dried up trap seals on plumbing fixtures. 

Don't fall into the trap of thinking you can lower expenses and raise rents with self managing to make the numbers look appealing to justify buying at a certain price.Of course you want to plan on increasing yield but if doesn't turn out like you want it should cash flow from day one.Those upsides to the property should be the icing on top of the cake and not the cake.