Condition is everything. if a bike needs tires, it often needs a tear down to replace old bearings and grease in BB, wheel hubs, and headset, new brake pads, freewheel will need a good flush, clean, and relube, chain may need to be replaced, and replace cables and housings.

People often under-estimate the extent of work needed to revive a bike. People tend to ride bikes to failure. Routine maintenance is not the norm. And a shop "tune up" is not what I am talking about.

Of all the bikes I have acquired over the years (more than 600), I have yet to have found one where the bottom bracket and wheel hubs were in ready to ride condition. Grease dries out, stuff may still spin, but its not in road worthy condition.

This list may sound exhausting, but its really not bad for the do it yourself type. If you take it to a bike shop to get this work done, you will be upside down on value even if you got the bike for free! We get such neglected bikes from shops donated to our co-op all the time. Bike owners get sticker shock on repair work ($75 an hour plus full retail on parts and consumables), so they give them to the shops. Then the shops donate to us, where we use volunteer mechanics and donated supplies to bring them back to life.