There are several things that are important to look for. A good drywall company will have experienced people who have years of experience with the type of drywall work you need done. While it's not overly difficult to just throw some drywall up, it is more difficult to make it strong and have it look good without wasting material, and that's where experience comes in. Little things like which way you lay the sheetrock can make a big difference later on. A good company should also use only quality materials so they stand up to normal everyday wear and tear without being prematurely damaged and needing to be repaired. Drywall finishing is more art than science and when done well everything looks seamless like it was always there. When done wrong, it will always be an eyesore and will reduce your property value. Badly completed drywall work tends to draw the eye. The most important quality is also the hardest one to see up front: attitude. A good drywall contractor must value what you want and be willing to do the job right, even if it takes more time or material. It doens't matter how much or how little you paid for the job if it isn't done right or doesn't look the way you want. Getting the right company to do the job the first time means saving money on hiring another company to fix it later.