cleaning ducts worth it?

[Aaron Carter]

Long story short.Bought a multifamily forclosure built in 2001 previous owner had up to 30 dogs and 20 cats. 

I scheduled to have the ducts cleaned but after reading more info online , research suggested that cleaning the ducts has not proven effective in reducing smell or allergies.  I was quoted $450 for the procedure. House is on slab, ducts are under the slab.

We have fixed the flooring which has fixed most of the smell. My wife, one month old daughter, and I will be living in the main unit as our primary residence.

Has anyone had this done and had objective results? Is it worth the cost?