It would be far too easy to dispute the price, make a huge fuss and get some kind of a discount. She knew the cost was fair - it was the sort of amount she'd been expecting, and as an avid motorcyclist, she was already well used to spending a pretty penny on keeping her bike in good shape - and she was itching more to get what she'd come for, leave, and get back to fixing her bike in order to take it out for an evening ride. The wallet that was produced was a man's wallet, leather and folded in half to hold cash as well as credit cards, of which Charlie only had one. She'd never been very good with numbers, and she figured less was more in keeping herself out of credit trouble. No fancy, huge wallets in purses for her, no, that was just ridiculous and over done and who needed to carry all that shit around anyway?
She pulled out two twenties (she always preferred to pay in cash - credit was a tricky thing, reserved for emergencies, mostly because she couldn't get past the idea that the money didn't belong to her and thus she was always wary of what exactly she was spending) and held them out over the counter for Idris' inspection. As long as he didn't do anything insulting like questioning whether she was using fake bills, this would be quick and painless and she'd be out of here fast. Though she was finding the garage to be very calming - for a moment she wondered why she hadn't gone for a career in car repair or structure, since it was something she was both familiar with and comfortable about. There was just something in violence, either the repression or enaction of, that called to her, making her want to salvage what she'd had in the Marines.