Furthermore, the majority of tenants here get Govt. assistance for their utilities so the impact is not always as significant.

I bought my primary residence in May of 2007, when the market was at it's height. Home values have dropped so much in my area that I cannot break even if I were to sell, so I intend to stay put for a couple of years, ...

Other items for example can be addressed that cost less and may or may not directly impact rent.

Not sure how assessments impact the costs, so any pointers would be great3.

My concern would be if you don't feel comfortable going to the house alone is this going to also severely impact the number of qualified rental applicants you would get for this property?  

Honestly, at the beginning it won't have much of an impact.  

Smoking is very negative to the healing process (blood circulation, clotting etc) and if this lady is older, her immune system while smoking will be significantly impacted...she'll be inside longer to recover even during the warm times...Look at your business and focus there.  

I can't give legal advice but it sounds like the cops are not enforcing the laws on the books.You can't have your center impacted because they want to be "lazy with the laws".If they are sleeping on your property they are trespassing plain and simple.

You should be able to compare to see what impact your extra payment made.

Portland is an awesome city that's on the up and I, myself, look forward to being an investor in this culture!