Whether its a windshield, hack out, or shower enclosure, your best bet to shed the profit pounds is to give it away to the customer. For most glass companies this is fairly easy. They've already had a lot of practice giving their profit away to suppliers so caving under the pressure of a "price-checking" customer is easier than falling off a log.
Key point: the goal is to break even.... not go completely broke, so be careful how low you go in trying to get a job. You don't know the overhead of competitors so you just might be pricing with respect to companies that are on their way to a bankruptcy.
How low is TOO low? Well if you're still in business and you can pay your bills, and live paycheck to paycheck it sounds like you have a nice break even company. If you are sooo busy you can't see straight... you might be one cash flow issue (or theft issue, or lawsuit issue) away from going OOB (out of business). If you do go OOB, don't worry... all of you low cost competitors will be happy to hire you for peanuts, after all they can't pay you much... they have to compete on price!