How to handle possible flea problem with vacating tenant?

[Lois S.]

All of my rentals have been 'no pet' properties, but...

I have a tenant leaving soon who brought in an "assistance" animal - a dog.

So I have a few questions.

If you know the tenant has a dog, do you require them to flea-bomb when they vacate?

I've been reading that all surfaces should be cleaned after fogging since it's poisonous.

I do require professional carpet cleaning on move-out, and proof of it with a receipt.

Should I let tenant know they are required to use a professional exterminator service in the house & yard?

Or do it myself after they move out & bill it from the SD?