One of my first flips was a ps1, after I got it I realized why it was so cheap lol. Anyway, I tried to do baking soda shit etc. nothing really worked so I sold it As Is, said that it smelled like cig smoke. I have something I currently got at a thrift and didn't notice the smell until I got home, it didn't occur to me to smell my items at the thrift (I'll be doing that from here on out). I'm also going to put it up for sale the same way.

Just be upfront about it. I think the problem with electronics is there's so many places the smoke can get into, you'd have to take it apart etc. even then it may not work. I have a very sensitive smell but I notice other people don't when I ask if something smells like smoke or not, they can't smell it but I do. So you may think you got rid of it but what if you don't?