Right now, there is a brisk market for used analog UHF and VHF narrowband compliant radios, both mobiles and portables. You are right that there is a lot of used gear coming available because many agencies moved to 700/800 or one of the VHF or UHF digital technologies. But, just as many agencies have simply replaced non-compliant analog gear with compliant analog gear so there is a scramble to scoop up this used gear, especially by folks that own their own radios to match what their departments have done.
I suspect you may see prices for used compliant stuff remain up a bit for quite a while to come. Right now I am on the lookout for Motorola CDM750's or CM200's in VHF, both 40 watt and 25 watt models. Used ones are selling for right around $150 each WITHOUT mic, mounting bracket, or power cable. If the accessories are present, most of them are selling for $175 to $190 depending on age and condition.
Eventually the market will settle down, but it's going to be a roller coaster ride for the present. Good luck with your search. If I see any UHF stuff at bargain prices, I'll keep you in mind. Any particular brand or models you want?
