I looked my house up on Zillow and it is showing an estimate of about $80k. My homeowner's insurance has it covered up to $75k, the county tax assessor lists the FMV as about $50k, and I owe $37k on it. My own estimate is about the same as the tax assessor's, and I wouldn't ask more than $50k when it comes time to sell it, given the work it needs to get it up to the Zillow estimate in my eyes.

Looking at other houses in the area, my house appears to have a much higher perceived vs actual value, based on Zillow estimates alone. For example, my neighbor's house on Zillow is supposedly worth $90k, but I'd put it closer to $100k based on her lot size, house size, overall condition, and age of the house (I'm friendly with my neighbor so I know a little about her property's history and makeup). In other words, her Zestimate is a bit lower than what a reasonable person would put it at, whereas mine seems greatly inflated. Perhaps this is due to Zillow "grading on a curve"; it would seem odd if one house was rated at half the value of its neighbors, so mine gets brought up to the lower end of the average range even though it doesn't deserve it. That's purely speculation on my part though.