Depending on if youve skilled it fully. If you have skill 1, put it to 0.5, if you have skill 2, 0.25, and skill 3, well thats tricky 0.166 or better go with 0.17
Some skills have set amouts for each lvl, some have a set amount for all the lvls.
Well, I've been trying to mod the shops as well without much luck...It never shows more then 3 weapons now, so I changed it back. What governs how many items the shop has I don't know, but if someone finds it, it would make the world of difference for modding shops. I'm also curious as to weather or not you can add things like blueprints into the shop and just buy them, instead of scouring the world for them.