In terms of rehab costs, they vary widely and you may end up needing much more than $20K. 

Going long distance is quite tricky as you are open to wide array of zip codes to choose from.

Definitely shop around - the variation in cost premiums is wide. 

But there isn't a lot of calculation involved, other than figuring out what your payments would be on different principal amounts, and any widely available online mortgage calculator can do this for you in two seconds. 

There are all types of visitors with wide ranges of budgets/desires coming into town for Derby. 

Now the tax assessments can vary widely, I’ve seen land value as low as 3% and as high as 65%!

Check out socketsite.comLuxury condos aren't doing hot in SF and there's some examples on that site that are interesting.I think the key here is that it's specific condos some of which were likely overpaid and now we're seeing true value but it's more of unique situation then city wide trend. 

He is correct that if you choose to do so, you should do it with your eyes wide open and know the risks involved.That said and done, I never counsel clients to do things that violate their loan agreement, nor do I ever assist them in doing things that violate their loan agreements.

In general, yes - an HOA has wide latitude in determining how properties are used. 

You’ll see how widely the values will differ.