Make it so we can "order material" when attempting to buy parts, upgrades, modifications, knives, with a few catches:
1. When Ordering Material, the cost of the part should be doubled or tripled.
2. It takes one mission or more before the parts arrives for the development.
3. There's a chance it may fail. When it does, you are given the option to withdraw the order or retry.
4. In a rare chance (and they should warn), the material may be lost/stolen before delivery, and in such cases part or all of the money should be lost.