Getting rid of super-strong pet odors in a rehab -your story?

[Lynn DeShazo]

I'm about to rehab a property in need of odor remediation in a big way - cats. I got an estimate from Servpro, it's so bad. Every scrap of carpet and pad has to come out. Floors will be cleaned and sealed, surfaces and windows cleaned. There will be an ionization and thermal fogging. I think the ducts will need cleaning too - $$$$

I was wondering if anyone on BiggerPockets has any experience with Servpro's  odor remediation services, another company you'd recommend, or if you have a story to tell about what you did to get rid of really pungent odor in a rehab or a rental. What do you think about having the ducts cleaned as part of the cleanup? I'm in central Alabama. Thanks!