Check out a Train AC you can get a 19 seer. But best buy is the Trane XL16i has a seer of 17.00 and with a heat pump of 10.55 HSPF. they do a better job of dehumidifi. For there and you are going to stay in the home long Id go for a heat pump for sure. look into it
For a filter dont go with a EAC kind get a good pleated kind up to a MERV 5 and put a new on in every 30 days. $7000 sound very high
ED
My .02 cents
My mistakes dont define me they inform me.