I like several of the answers you've already received, and I'd like to take a moment to expand a little more on Brian's point--especially as it pertains to investors.
He's absolutely correct that many investors, who know what they're doing, will only purchase properties at wholesale prices. He's also correct that this figure often--but not always--comes around 65% of the ARV (the after repaired value or the market value of a property after it's rehabbed). Sometimes that figure is higher (if less repairs are necessary), and sometimes it's lower--especially if the property was trashed.
The point here is to acquire an investment property using a viable exit strategy--meaning one needs to know what one plans to do with a property before buying it. Also that exit strategy better account for any and all acquisition, rehab, holding, and other costs. If one intends to hold that property for a while, then one needs to ensure that one will receive sufficient income from that property to be able to service its debt (ie pay the mortgage) and cover all of the expenses. Ideally, after having serviced the debt and having paid all of the expenses, one will still have something left over for income (aka positive cash-flow). Otherwise, s/he will end up subsidizing that property from other source(s) of income (which is typically one's take-home pay). Yet, if one intends to flip that property, then one needs to ensure that one will be able to sell that property--after it's rehabbed--for enough to account for the acquisition, rehab, holding, other costs, and one's profit.
So, think about what it is you intend to do, and then you'll be able to determine better what a good price will be for you.