As previously mentioned, foamboard or panel insulation cut to size around the base of your unit is what I have seen used up N for FT'ers. I think they also make a window insulation clear. Like used in S/B.
We recently purchased Dyson Hot/Cold fan for our RV. Has a remote, set temperature, motorized swivel option, variable fan speed, very nice but also pricey.... $400
06 King of the Road 37RLQS
06 Coachman Cross Country 5.9L 300HP 382 DS
03 Jeep Wrangler, 4.0L James, Trina, SMSgt, USAF Ret