The air conditioning unit on the trailer continues to produce some cool air, although not as much as we know it's capable of producing. Combined with it having iced up a few nights ago when there was a brief spike in overnight humidity, we think it's simply low on coolant. We found the service manual for this model online, and it appears to use R-22 coolant. While you can't build new R-22 air conditioners anymore, it's legal to produce coolant and recharge older units (as long as you carefully recover any existing coolant for recycling) until 2020. Therefore, if the A/C repair company can do so, we'll have them recharge the unit and worry about replacing it sometime in the next decade. We hope.
In the meantime, it's a couple of degrees cooler today and cooling just slightly here in Fernley, although still unpleasant in the direct sunlight. Lisa moved one of the insulation pieces that we were using last year to seal the south (unheated) end of the house over to the living room to partially cover the windows. Basically the only fully-inhabitable room in the house is the living room and that state of affairs will continue until we can scratch up at least $5K.
Yes, I reckon we could probably afford the repairs sooner if we'd skipped Westercon (except we needed to get Lisa's stuff from Oregon anyway) and if we didn't go to Worldcon. It's a tough call.