"Always the low price" may work if you're Wal-Mart; for the rest of us, its' suicide.
If the 'going rate' is somewhers between $800 and $100, there might be room for you near $800- but I doubt it. Down at the bottom of the range, there is no room for errors or complications; below that range, you're in danger of subsidizing your customer. Go much below that, and folks will wonder what you're leaving out.
We've all seen the tire ads for $30 tires. By the time they finish adding all their charges for mounting, balancing, disposal, etc....they're no cheaper then, or even a bit higher than, the guy who gave you the "$80 and out the door" price.
You have three things you can sell: price, service, and quality. Sell on price, and you cheapen your work- you make it a commodity. You are saying, in effect, you're no different or any better than the next guy.
At the upper end of the range, customers are going to expect more....things like service tomorrow (rather than three weeks from now); that you fix your sheetrock holes and clean up your mess; and that you don't look like some street-person working out of the trunk of your car.
Just as not all contractors are identical, neither are customers. Save your "sharp pencil" for the guys who are prooven good customers; that is, they produce repeat, steady business, and pay promptly.
