While I think a good number of companies will relax their work from home policies, and newer companies (start-ups, small businesses, etc.) will re-think the traditional 9-5 structure, I don’t think the traditional 9-5 way of doing things will disappear anytime soon.

Do the leases have to be re-signed with information regarding the new policy included?

You mentioned being worried if your tenants don't pay rent.....you should look into one of the cool products my company offers called rent assure, where basically you can take out an insurance policy on your tenant so if heaven forbid your tenants did default that you would be able to get reimbursed.If you build the right team around you a lot of those worries naturally go away. 

Now in 2018, the HOA is just decided to enforce its policy and wants the dish removed to a different location. 

Usually you simply add the lender as a Mortgagee on the fire policy.

However, the lease does not have a smoking policy at all.

I've read several articles and discussions about how intentional damage from a Tenant is not covered under landlord insurance policies. 

I would consult with your insurance agent to see what are the details of your policy regarding the dogs.

In fact, that was my policy... since they (students) generally didn't have much credit and many didn't have jobs.

Ask your particular servicer what their policies are when you create an account with them.