Get rid of anything they could eat. They’ll soon disappear to somewhere there is food.
We had rats in our garden for a while. They came after we hung up a bird feeder and we saw them munching on it from the kitchen window. We got rid of the bird feeder and haven’t seen any rats since.
I had rats in my loft. Trust me when I say if you have active rats in your loft you will know all about it, they make A LOT of noise. The council came out and put poison down and that got rid of them. I didn’t feel bad, they were chewing through all sorts and I would’ve felt worse if I’d ignored it and it resulted in a fire.
One thing you can do is search for how they’ve got into the house. Normally it will be a vent covering that has come loose or something similar.
Govt. Guidance on tradespeople says they can if they don’t have symptoms, maintain 2ms social distancing and wash hands when they’ve arrived.
They could make an argument that exterminators would fall under sanitisatiom and possibly be key workers.