Talk:Research & Development/Fenyr Supersport/@comment-220.227.103.136-20160818192715/@comment-29494139-20160819165530

Currently my inventory storage is 620. From earning stars and purchasing +20 storage a few times. Here is the rule I use for card boxes.

I have been playing this game for a while and I already max proed most cars I own. Before I got into this stage, I tried to use all the cards in my inventory to pro upgrade any car I own, including not so great cars.

My rule for opening boxes: I do not open boxes in which I am sure what is, e.g. "mid tech box" "V10 engine box" etc. But I open boxes in which I am not sure what is. e.g., "tech card box" "random box" "B class parts box" etc. By doing this I can always tell what cards I have in my inventory. I do not leave random boxes unopened simply because I don't know what is in them.

My rule for selling cards: I sell unneeded and common cards, such as lower end parts cards and initial&early techs. Of course I always keep some of them, like under 10. I never sell any engine card, regardless of rareness. I do not sell rare&legendary cards such as A&S parts cards, mid-advanced tech cards. I sometimes sell A&S cards when I have too many (like above 40).

I'm not sure if this is the most efficient way of keeping the inventory, but it doesn't seem to be a bad rule.