It monitors temperature, humidity, and electricity.

Smart investors monitor this an as it goes below 10-15% they sell or refi and releverage.

That's my strategy, I hold a larger stock portfolio in index funds to accelerate growth, and monitor deals to purchase.

At end of the day the houses are your responsibility and you need a way for your tenants to get ahold of you.The way I look at it is that it makes life easier for me not to have an extra email or vmail I have to monitor.   

Anywho....The cards monitor your credit the whole time you own them.  

I don't see any point in paying a monthly fee for a foreclosure monitoring service.Even if you're hoping to market to the owners in pre-foreclosure, 1) so are hundreds of other investors, and 2) this information is public record (just do a public records search for a Lis Pendens). www.hudhomestore.com and www.homepath.com list HUD and Fannie Mae foreclosures, respectively (but even these are also listed and sold through a listing agent on the MLS).As far as price, every deal and every property is different.

@Ryan Plesz & @Courtney M.I use local market monitor.

You can also put in a camera to monitor if you are really concerned. 

Could it be hard to evaluate a contractor for rehab work and monitor their progress?

I don't always monitor all of these forums on which I post comments, it would be too many.