Before you go swinging that kind of money around -- better find out if they are worth renewing. I tell you right now that if you just bought them last year, unless you had some very special way to find them, that many, most, or nearly all of them are not worth it.
Post some for appraisal - or (much) better yet try to sell some. Use that knowledge and the hit/click data from parking to make your decisions (if you have not had them parked even a few weeks can give you an idea of the traffic). It is not easy to let go. It is the .info trap and we all fall in - the trick is finding the few gems that will make it worthwhile.