I'd read up on the law to be exactly sure but, if it is as it is simply stated in the report, ownership is what it is. I think you should pay your $.02 prior to the item being acquired so that it can be clear that you actually purchased it. I think that it really is important that you have a partnership agreement of some type with your clients. Nothing complex but, it would need to state that you pay for (some or all) items with common ownership. If the client wants to own a common item completely, for whatever reason, the client should have to buy your $.02 ownership. The Small Business Admin. should be able to give you a chance to chat with a lawyer for free in a class type setting.
Also, I wouldn't collect $.02 from the clients on sold items. I'd do $.07 or something. You'll have items that do not sell that you paid $.02 for and you don't want to make an easy trace of funds that can be used to challenge your ownership.
Countermeasures are always cheaper and easier than the measures they defeat.