Sometimes, sometimes not. Mobile welding has a service-call component that fixed shops don’t, but it saves the cost of trucking the equipment, the time spent loading and unloading, and the lost production while the equipment is gone.
For most jobs, especially anything heavy, immobile, or already on-site, mobile welding nets out cheaper or even. For small parts that fit in a truck bed, a fixed shop might be cheaper. We tell you which makes sense for your situation.