I thought to have an FFL, you could not work it from your home. I was told you had to have a store front for the business. I carried an FFL in TX for many years, and the cost increase (free when I got mine), and having to have a storefront caused me to relinquish mine.
As for the KSL ads, I just automatically select "Individual" every time I browse the firearms section. This will remove Clinton, Provo Pawn, AF Pawn and several others starting to fill the sections with 20-30 ads per listing.