Are you wearing clothes in your profile pic?

For the interior, use drop cloths to cover the floor.

The place was total chaos, I couldn't barely see the floors with the amount of clutter and clothing everywhere.

If the walls are still damp or you create a situation for mold to grow, the oil based primer is made of organic compounds, mold is organic..you are essentially giving it food, and the primer seals the wall so there can be potentially mold growing behind the film of the primer.

The Purchase:Purchase Price: $224,900Loan: 25% down ($56,225), 5% interest, 5 year term, 20 year amortizationClosing Costs: $6,150 (received $5000 sellers assist)Repairs Budget: $15,000Total Cash Invested: $77,375The Income:Gross Rents: $4,500 (estimated after repairs and full occupancy)The Expenses:Property Taxes: $500Management (10%): $450Insurance: $225Natural Gas (both clothes dryers are gas and surprisingly they're the only things running on it): $40Vacancy (5%): $225CapEx & Vacancy: $405 (estimated, don't ask why I have $5 at the end instead of an even number..I'm going off my previous work so who knows what I was thinking at that time)Electric (common areas): $100Water & Sewer: $375 (there is a very small water bill to me as each unit is separately metered.

There was a strong damp smell and I thought it could be wet surroundings or possible signs of mold.

One house had some insulation added under the floor.I still have to get out and put some flashing on a shed where the tenant told me the wall got damp when it rained over the summer.I had a backhoe out to replace a culvert under a driveway.Unfortunately, I get fairly frequent turnover and each house is completely repaired down to the last screw tightened between tenants.

It's a set weekly amount and I withdraw the cash the same day every week.We have a budget for everything - haircuts, clothes, fun, airfare (emergency as we live 2000 miles from family), vacation, vehicle maintenance and inspection and registration even.

The super has last seen them  2 weeks ago, and noted that the tenant was not wearing regular work clothes, as they normally do in the morning, waiting to catch a ride to work. 

They all bought expensive cars and expensive clothing, now most of them are back barely able to make the bills and are now working a 9 to 5 job.