Most LA charge by the square inch. A simple all over repeating design like a pantograph or simple meander is usually .01 to .015 per s/i the price usually goes up from there. So say you find a LAer that charges .015. If you have a queen size quilt that measures the average queen size of 90" x 108" you multiply 90 x 108 for a total of 9,720 square inches. Then you multiply that by .015 to get a cost of $145.80. This price is based on you providing your own batting and backing but many longarmers can provide these as well for an additional fee. If you want the quilt custom quilted the price goes up incrementally depending on the complexity of the quilting. If you go to Green Fairy's website she has several examples in each price range.
http://greenfairyquilts.com/pages/-L...neQuilting.php