Thought I'd chime in here with a comment and maybe a couple of questions:
My fairly nice '89 325is has a
very slow leak (through the evaporator, IIRC) so I've just been charging it every couple of years with R12 at a local shop. Last time it cost about $150, so it's a bit spendy for a 22 year old car worth maybe a few grand.
I'd rather not replace the evaporator ($800) but it is also getting tiresome spending $150 every other summer for R12 and I really like cold air in the summer.
Is there an off the shelf product I could buy to do this myself? Propane? Freeze 12? Something else? Should I have a shop evacuate the remaining R12 before the switch? I'd rather not convert to R134 as that would cost almost as much as replacing the evaporator, and from what I've read, won't cool the car nearly as well.
I'd tell the next owner of any changes I made, of course, but I'm guessing the next buyer of my car would be amazed if the A/C still worked at all
/hijack