Professional woodworkers often don't use pads on their clamps because they know how to set them up without marring the wood. But if you prefer to use them for pipe or bar clamps, you can buy some or make up your own. Scrap rubber, shoe soles, even old mud flaps, can do the trick. For pipe clamps, cut out a slightly undersize circle to fit over the pipe using a sabersaw. Next, cut out the perimeter about 1/8 in. oversize. Then make a slit in the pad bottom so it can stretch over the pipe without taking off the jaw end.
When hiring a roofing contractor, the lowest-bidder is not always the best for the job. Roofers with good insurance, good safety equipment, and well-trained, skilled employees charge more than fly-by-night outfits, and rightly so. Quite often, that roofer will have a standing relationship with a reliable manufacturer who puts out a good product and backs it up. Check the insurance, license, professional certifications, and references of any roofer you interview. The right shingle and the right roofer will make for a lasting job.