@Andre Williams Depends on how much their owe on their mortgage.

I'm installer of user of direct vent fan with humidistat. vent heavier moist air near floor, and replaced by air exchanges min 3 per pp x day. installed $1500-$2500 vents  aprox 2000-4000 sft. depends on region and avg humidity levels. a whole active not passive cs basement vent 230cfm more. installed into wall is vent like #1,  with 3-4 manufacturer's in no.

It depends on what you're trying to do with your investing.

It will also depend of where you are at in investing.

The entire exchange period is only 180 days so the max your money will be tied up is an additional 135 days.And there's another silver lining - depending on how the dates line up your 180 days may not end until 2019. 

Most of the experienced ones will be able to give you a ballpark per SF as a starting point, which may vary depending on price point and therefore level of finish out. 

It all depends on how you buy it (FHA, conventional, cash, private money etc.)

The answer may vary by lender and would likely depend on how that income is being reported.

If so, and again dependent on local laws, the trustee may be able to redeem the property from the tax sale. 

Completely depends on the location of the propery and the type of loan you are looking to obtain.