Bane Spider Tau

So earlier today, someone accidentally double entered the influence they were trying to put in for an IO I had for sale, so it went for 400,400,000 instead of 400k. By luck I was able to track them down, but we got to talking about how we both felt how easy it is to accidentally do that kind of thing, and how nervous I am about it when using the AH. So I was wondering if we could have easy to input bid caps on the auction house, so we don't accidentally add a zero (or 5) to a bid.