How do I know if this is a good buy?

[Pam N.]

I am looking to buy a condo in downtown Minneapolis, how do I know if something is over priced? I found a property through a real estate broker website and I've looked it up on the county's property information website. The county has the total value as $97,500 (taxable value is 67,035) but it is listed for $150,000. I've looked up a couple other condos and they are all listed over the county's value like this. What does this mean?

Also, the broker's website shows comparables from late 2012/early 2013 and they seem significantly cheaper. Like $50-80,000 cheaper. Does this mean downtown Mpls is overpriced right now? This is my first purchase and I really don't want to start out under water. Would it be better to wait a couple years for the next recession?