Yup, Like Utra Violet said.
You walk into the clothing store and buy that nice protective armored jacket that you've been eying for a while. It's still in style, you saw it last week at a different store, but this store has it on sale (easy to get Avail 2). Jacket in hand, you leave the store and realize you really want some Chemical Protection for it...but crap, you have to drive down to Tacoma for the shop that specializes in after market protection applications (harder to get, but still legal Avail
. You make the drive, hand over the jacket and as they're applying the protection you realize that you'd just love some Shock Frills and Thermal Damping so you strike up a conversation with the shop's manager. He says he doesn't have the ability (or the licenses) to do either, but if you've got a license for the Shock Frills (restricted rating, Avail 6) he can set you up with someone that can do it just a block over from where you are now. For the Thermal Dampening, they only do that for Lone Star/Knight Errant employees or some special ops out of Fort Lewis (forbidden rating, Avail 10). Each of the Availabilities are separate.
Now if you walked into that clothing store and wanted Feedback Clothing option on the jacket...you'd have to custom order it, it would take a while but it's perfectly legal (+8 Avail, so the Jacket is now Avail 10).