Personally, I dislike your houserule, simply because I am a gear whore. I lovingly and painstakingly comb through the gear portion everytime I make a character (and then have to relovingly and painstakingly comb through when I forget lifestyle/fake SIN/some other essential piece). However, the rule is quick and dirty, so it'll make creation that much more streamlined. I would go ahead and make them buy it as a skill depending on how broad you wanted to make it and of course they couldn't use it for certain gear like Cyberware, Vehicles/Drones, Weapons/Explosives (your choice on these, but I would make them choose these on their own), and Magical equipment (no pulling Arcane Labs and Lodge Materials out of your backside you know). If you leave it in the realm of knowledge skills, don't let them use their freebie knowledge skills on it. I know I'd just take a 6 and specialization in it so I would be unlikely to be caught with my pants down if you did. It'd kind of be a no brainer because there's nothing to fear if you've got the gear. By making that 6 cost them 12 build, they paid a good bit to make sure they had their hoops covered, and I think it's a fair trade off. Of course, your game man. As long as you all have fun, who can say you're doing it wrong. Also, make it limited by Threshold (based on rarity of item) and if it has a rating assigned at it, they get a Rating 1 for meeting the threshold, then each hit they achieve beyond the threshold raises the Rating by 1. If you allow them to use it for high value itmes, you could make it equivalent to meet Threshold = 5,000

value and each hit beyong threshold increases it 2,500 - 5,000

more. Just a thought to cut back on the, "Ooooo look, I have a Rating 6 Agent on my tricked out com with 6 attack and analyze."