Like stitch in the ditch quilting? Even faster would be tieing them if they're denim etc. I don't tie quilts as I love the quilting process, but would make it easier and you could charge less for less time involved. Something to consider.
I don't know what others do for lap quilt measurements, but we are small people in our household. I make them smaller than twin size, but larger than a crib. I think a general guideline would be around 50" X 72" plus or minus an inch or so. I usually let the quilt I'm making decide the final measurement and I can add to it if it's not large enough with a border.
Most people say charge about 3X your material costs.