Here's a tip @Asury Johnson, when nobody is immediately checking in to a STR after a cleaning we make the beds with the damp linens right out of the washing machine.

Being a general contractor and an experienced investor I see stuff from multiple angles and the key component of what you said was he is selling this property in the winter and that's exactly for a reason I've seen this happen many many times.

If her home is close to the retirement home, perhaps people could stop by the vacant house on their way to visit grandma or stay there if they live out of town and are visiting grandma.I'd also disconnect the washing machine.

They always gave preference to cosmetic issues like landscaping and power washing instead of issues that are hazardous and code violations.

You may have income from wash machines....Each eviction assume $1K taking some time so plan on 2 months.

Do you have a dishwasher or wash by hand?

This jives with my recent experience listing an upcoming vacancy (2/1 in a Wash Park West triplex). 

Totally fine if you can continue to fund for say 5-7 years, but as we saw in 08/09, lots of people expected endless price appreciation and when rents softened they were washed out (how I bought my MF).  

We plan on house hacking the bottom unit while we do the repairs and within the next year or so, purchasing another multi-family property to wash, rinse & repeat.Financing was done through Navy Federal Credit Union, where we were able to put down 15% on a 30yr conventional @ 4.5% interest rate - with closing costs, we're looking bringing ~15k cash to the table.   

Rinse/wash/repeat.