I've not been on BP for long, but I've already noticed something disturbing. There seems to be a lot of newbies who actually believe that the "Zestimate" on Zillow is useful. Or even worse, that it provides an ARV for a property. Zillow's own data (you can find it yourself if you search their site deeply enough) often indicates that their Zestimates are often 20% or more off-target for a given county. I would say that the online estimates from other websites such as Trulia are equally as suspect, and should not be trusted.

I am also a Realtor and I don't even have words to tell you how much other Realtors and I HATE Zillow. We have to deal with people all the time who say stuff like, "well Zillow says it is worth $xxx,xxx". Then we have to say, "OK, then why in the hell hasn't it sold in 978 days on the market at that price if Zillow is so friggin smart?". Seriously, if you can't learn to do comps on your own, if you have to rely on Zillow, you're not ready to be an investor yet in my humble opinion.