They might not have the budget for a STR on par with our normal rates, but perhaps at a significantly reduced fee, we can at least get some incoming cash flow to go towards the mortgages, and they get a clean, private space that they wouldn't have otherwise been able to afford. 

I think an appropriate mask and eye protection limits your risk but mainly reduces risk to others from your aerosols.

More of the thing to consider is having reserves to cover the loans on all your rental properties, and a 3-6 month emergency fund to pay for your own home and life should your income get reduced a bunch.

Can anyone advise what specific charges I can dispute or reduce within the closing costs of a refinance?

I will work on a case by case basis from there to defer or temporarily reduce rent.

Perhaps working out a bit of extra time to pay rent is realistic due to circumstances though asking for a reduction in rent is nonsense as lenders won't be reducing mortgage payments nor will tradesmen be lowering their prices due to the Corona Virus. 

I am thinking organizations that will help them pay rent, utilities, etc.One that I am aware of is Catholic Charities: https://ccdocle.org/program/emergency-assistance-servicesPlease add to this thread as you see fit; we can all benefit from this information being shared with our tenants to reduce the impact on our clients.If there is already a thread about this in another forum (current events, landlord forum, etc) that I didn't notice, please let me know/link it here.Thank you!

If our numbers trend at a flatter level, it will reduce panic and could stabilize this as we fight through it.

Maybe it’s the lenders overlays preventing them from approving it?

Using a HELOC to invest in other property is a good idea if you know that you can handle the payments but remember your mom would be using her house as collateral like you said, HELOC's have a variable interest rate and you would essentially be reducing the equity in the house.