use "Kilz" , its the best stuff , wear protective gear. its harsh and may cause light headedness if not well vented
Kilz is a great product! We also have 2 ozone machines. If there is any smell from pets, smoking, unique cooking seasonings, we run the ozone machine for about 48 straight. You can rent them or buy one online. I makes the whole house smell like an intense cleaning solution was used. Just open the windows and doors when you are done and air it out. It really helps with smoke smell.
I second Kilz and the O3 machine. If it is as bad as you say, don't forget to change out the blinds, wash all windows, ect..
Thank you all for the advise, I will try all of these options to get the smell out. I actually used the Zinsser odor killing primer sealant the other day, and that seemed to help the best so far. It got rid of the heavy smell, but you can tell there is still some lingering around.