The entire pricing issue continues to overlook location / market areas. If company "A" can actively sell the same product for 25% more than your market will bear then they also should experience higher operating costs. Cars don't sell for the same thing across the country, nor does milk. Your market is yours alone.
I believe the pricing question is what inevitably keeps this market alive and kicking for smaller shops (like us). The optional ways of creating things like a banner vary greatly. Yes they are all still banners but base materials, application, printing / cutting and other variables will never allow a "set" price for such items.
As stated above if you make every sale you are doing it wrong. And let the bargain hunters can go drive someone else nuts 5 states away. My favorite is when they tell me what it will cost....hmmmph.
BUT yes there are always the ballpark price questions and more often than not a simple $7 sq/ft answer will establish if they are for real very quickly.
Break down your costs, lights, heat, equipment, materials, shipping, waste, labor, insurance, grief, rent ( we use a 40 hr work week to break those numbers down to "operating time") and anything else you can think of then triple that number for cost per square in. or ft. to determine what it costs you.
The tripling method goes like this, let's say you calculate $1.00 a sq/ft (nobody snap it's just a figure), the second $1.00 is for things unexpected or rare (repairs, upgrades etc.) and the third $1.00 goes to waste and errors. Then we take the final figure and add a profit margin.
Right or wrong that is how we determine pricing.
Hope it helps, and hope the bashing isn't so bad.