I have built enough capital to feel comfortable investing heavily and am interested in either a flip, small multi family, or commercial.

The property taxes will be on his Schedule A during the time the property was his primary residence, assuming he itemizes.

Built in 1961, this residence offers 4 bedrooms and 2 bathrooms within approximately 1,500 square feet of living space.

Also, how old are your capex items? 

Hey all, I currently have a new home being built that I would like to keep in my personal portfolio.

Taking real time notes on deficiencies allows for clear understanding if the items make their way to a buyer repair addendum.

The main house is original (this place was built in 1924, very cool) and we rent it for $1,650/month.

Assets identified in this study include:Appliances: Dishwasher, microwave, oven refrigeratorInterior Finishes: countertopsFurniture and Fixtures: shelving, built in cabinetry and decorative light fixturesSpecialized Equipment: Electrical systems and specialized wiringHVAC controls and specialized components63.6% of the total depreciable basis was classified as 39-year class life.

This is true for bonus depreciation items as well.  

The AP has to be open, notorious and hostile...those terms have a legal meaning and essentially it is that you as the owner have been fully deprived of your right to the property.Absent those items above, it sounds like at best they have another legal right which is a "prescriptive easement".