Nathan.. for 100k I would not worry about a phase one myself.. your personal inspection should indicate any potential there.. same with encroachments.. these parks are usually courtyard style on rectangular lots.. but then again out your way it could be meets and bounds.. which could be different. 

. - this will give you an indicator and a comparison of prices in your marketing area.Your goal should be to become super knowledgeable on value in your area.

FYI- with your days on the market, chances are you will not receive a full price offerNot sure why some are questioning whether you are on the MLS as a quick search of Realtor.com indicates that it clearly is listed on the MLS

Looking around on Zillow at what other properties are renting for is usually a pretty good indicator but keep in mind that the majority of people are just looking for cheap rent 

Poured walls usually indicate not too old and if the problem is that significant it may not be worth the trouble.

Certainly up-coming neighborhoods can be detected, but with what I know they are lagging indicators.

We all noticed a shift in the economy lately but in my opinion these are indicators that suggest only  a slowdown of the economy, not a downturn or recession :) 

In So Cal I was surprised that the cap expense was as high as the worksheet indicated. 

There's no indication that this property is FSBO.

If that had indicated otherwise, the seller would be liable.Best of luck!