Excessive smell - Final Walkthrough - 2 days prior close!

[Mety K.]

HI - I'm closing on my first property in 2 days. I did a final walk through inspection today and the place smells excessively! What should I do? The agent thinks the smell maybe from a dead mice or squirrel and that I should contact an exterminator to take care of the problem.

Anyone have had a similar situation? 

Do I go to the seller and ask a refund? 

Thanks!