Ability to Collect Payment on Quotes

It would be really helpful for any future updates to be able to collect payment/deposit on a quote. For accounting purposes, we collect payment upfront for goods so we can order. We usually don't send a final invoice to the client (and report the total for tax purposes) until after installation - that's when we add sales tax and shipping to the initial quoted amount as well. If we can't collect payment on a quote, we'll have several different invoices for each project and it's not very clean - accounting-wise. Just a suggestion that would be helpful in the future!