text: how do i figure out a bid for a used greenhouse, if the owner has no idea what their worth?  built in the 80's they were built in the 80's.  made of polycarbonate, mostly aluminum frame.  wood supports need replacement, and we have to disassemble and move it ourselves.  any info, including but not limited to how i would go about approximating what i should offer per square foot would be really helpful. the houses are in fairly good condition, minor repairs only thanks, amy do not buy it.