In the context of the story I believe that the mobile home would refer to a manufactured home located within a trailer park community. It's mobile until it is i

In the context of the story I believe that the mobile home would refer to a manufactured home located within a trailer park community. It's mobile until it is installed in the park and after that it is a stationary home, maybe even on a lot that they rent from the park owner. Though these people seemed to be retirement age it sounds from the story like they are tied to their home due to mobility issues so that makes it less likely that they were living in an RV or camper van. The costs of replacing an AC for a mobile home in an established park would be high enough that they would probably need to get a loan if they are on a fixed income since the home likely has central heat/AC. If they had been in an RV or camper van the costs of replacing those units is considerably lower. This is very sad to me. It sounds like their central heat/AC unit failed and they decided to replace it instead of going to their big box store and buying a window mounted AC unit that would function for the summer allowing them an opportunity to set aside some money to pay for repairs or replacement of the main system unit. Poor people in a rich nation. Over a barrel needing repairs or replacement of an expensive item that is critical for survival this time of year.