I am a mortgage banker though so I have a little more knowledge than the man/women on the street. 

I'm a strong believer that between basic security measures, common sense, and not involved with any drugs or gang activity, you'll have no problem staying safe. 

If there was two townhouses that had the same square footage, age and neighborhood (some in the same subdivision/street) and one was a 2 bedroom and the other was a 3 bedroom, approximately how much value would the additional bedroom be worth as it relates to comps?

I can target by zip code, street name, or a custom "bounding box" of your choice. 

Bid 4 assets and Grant street group are two that run tax auctionsI set up keyword alerts here on BP for "tax sale" "tax lien" "tax deed" and "tax certificate" I get notified whenever one is mentioned.

Im sure you have heard this before but please pay attention to the street and not a whole neighborhood or zip code.

Agree with Lance, driving up and down each street in south city is the best way to get a feel for the neighborhood.

Don't put in the street number. 

They turned  to the main street.

Union City is an easy commute to NYC and the Mayor (although controversial) has done a lot to improve the city like repaving sidewalks, adding trees and nicer street lights and adding parks, pools and sprinkler parks.