What do u think one of the earlier shoebox compressors are worth with five rebuild kits and a extra belt it is currently in working condition I need to clean off the grease that has started to pile up it's been rebuilt once and greased every 2 hours like it is supposed to be I'm going to try and sell it since I purchased mch 6 coltri also have 1 working yong Heng and one only builds up to about 1000 psi I think I'm going to sell also one as a parts and one that works any ideas on what there worth now? thanks