Definitely prevent moisture.Lots of places on the internet will give stats on which remodeling projects have the highest ROI.Some of my favorite (but less talked about) super cheap updates that get noticed by tenants or buyers but won't necessarily boost appraisal.

Would you give her a longer notice to find a new place or just leave her be?

Will there be any ahead after being caught back up in payments and repairs and holding costs?

Go ahead and use that VA loan. 

But if you don't have to deal with the current rents much longer or the units are vacant, than I would say go ahead and enter a conservative estimate of the future rents at market value. 

Please share your experiences with me so that I may stay ahead of the curve and learn from others mistakes.

I stress-test my budgets this way so I can take precautionary measures ahead of time.

But I keep an eye on it because it's so close to my market and notice some duplexes going for about 140-240 renting for around 1200-2000 depending.

The current lease is month by month for either party (30 days notice).  

I will make this well-known before they sign the lease in the first place.If they follow the rules, great.If they don't, they get a 60 day notice to vacate and I find a new tenant.