1. My AC isn't working in my recently bought 83 240D. Before recharging, I was wondering Freon 12 is so expensive, why not convert over to CFC134a? Are there kits to do that?

2. My 83 Volvo I bought with 171000 miles on it has AC like brand new. I don't know history of the Volvo but I assume its the original AC. Since the Mercedes I bought at a gas station appears to have been well kept by the dealer (M-B filters found on car) should AC, though empty, be okay for recharge if it holds a vacuum? (Freon12 is expensive!)