I have a 3.5 ton SEER10 Goodman gas electric packaged unit in my 5 year old home. The AC section lost practically all of its freon. The original installing contractor came out and cleaned the AC coils then recharged the unit but I have no idea how long it may take for the freon to leak out again. He used a sniffer and the long, flat coil is leaking freon. I plan on moving to a larger home within the next three years so that intent effects which way I go. In my previous homes, I used to recharge the AC until it got too frequent before replacing parts or the the whole unit. I have a quote to replace the leaking coil assembly which is less than 1/4 the cost to replace the whole unit. As an aside, the heat exchangers are still good but the compressor makes a minor high pitched metalic sound while running.
Should I repair or replace the leaking coil (and can that be done reliably at my home) or just go for it and replace the entire unit with a new SEER13 model? Obviously, if the compressor goes out after a repair job then I made a poor choice going the repair direction. Any thoughts are appreciated.