I just shut my cats in the bedroom, and the realtor told people they were in there, and to make sure all outside doors were closed. I think they just hid under the bed or in the closet. No one escaped.
I also bought my last house with dogs in it. I remember being slightly afraid to go in, since the realtor didn't know them, and the owner wasn't home. But they were Chocolate Labs, and the were so friendly and sweet. Not great guard dogs!
I think they made me like the vibe of the house even more. So, don't worry about it too much. It will work out.
'02 Eddy Merckx Fuga, Selle An Atomica
'85 Eddy Merckx Professional, Selle An Atomica
'10 Soma Double Cross DC, Selle An Atomica
Slacker on wheels.