We buy our R-12 for our coach on a Craigs List. It’s sort of a strange transaction , meeting someone in a parking lot, but it beats paying a shop $60-80/pound We bought a 30 pound container (sort of looks like a BBQ Lp bottle ) for three hundred dollars,mand another for $3750
We have vintage cars that utilize,R-12 for A/C, as well. Before we knew better, we converted two cars to the newer R-134a,,,let’s say we won’t ever do it again, and never the bus. We have been told old style low pressure compressors don’t utilize the “new gas” as well. The new gas molecules are smaller than R-12, and just leaks out of older lines and equipment. Changing out the bus equipment we have been told is very expensive, so we will stick with buying our R-12 meeting the seller in a cornfield. The two purchasers we met have been licensed refrigerant techs. We then take our containers to Stewart-Stevenson for install in the bus, only paying labor.