I've done quite a bit of research on this lately when I bought several water heaters...my thumbnail conclusions:Tankless are good in theory but can have issues if the hot water capacity is to low, so when comparing prices make sure you look at that.

Compare all expenses.

I just keep an eye on Craigslist and Facebook to see what comparable houses are going for and price accordingly.

The condos 1 mile away might be too far to be a true comparable. 

I was keeping it  thinking well, but its going to appreciate so much because of the aforementioned reasons...however, the appreciation won't happen fast enough (for me) compared to what i can do with the $$ elsewhere. 

I'm always willing to help a bigger pockets member out, I can run a quick comparable for you.

Not much to compare to this one.  

Otherwise, show the repairs needed to bring the property up in standards with comparable properties, then the costs to do so.

Then get comps on the rentals in the area, again make sure you are comparing eggs to eggs not to apples.

Something like maybe a website or maybe have actual meetings where we could compare notes, share stories and blackball deadbeat tenants like the apartment landlords do.