Mouse Infestation - Tenant Reimbursement?

[Art Maydan]

I have a triplex with an ongoing mouse issue I'm dealing with. Only the top two units have mice. I've done a lot of sealing and had an exterminator come out several times, so hopefully they'll be gone soon between what we're doing and it warming up. One of the tenants has two cats and a dog who catch the mice, eat them, and get sick. They're asking for some kind of compensation. The vet wouldn't provide a letter saying the pets got sick from the mice. It does seem like the right thing to do to pay them something for putting up with this issue over the last few months. I've told them I appreciate them working with me and agree some money paid to them would be fair, but let's wait until the issue is definitively concluded first and then we'll evaluate.

1. What amount would you pay? I was thinking $300-$500. Rent is $1,800.

2. The second tenant hasn't asked for any compensation yet and hasn't had pets get sick. I'd like to avoid them finding out I paid the first tenant and wanting some money too.

3. What are the legal implications with this? Should we sign some sort of addendum? I'm doing everything I can to remedy the issue. How else can I avoid liability?

How would you play this?

Thank you,

Art