It is very expensive to hire an H1-B compared to a US resident. The only way for it to be cheaper would involve fraud: paying a worker less than prevailing wage, which would require cooking your books, lying to US Immigration, and getting into a lot of trouble. (As is the case for a few big out-sourcing companies recently)

Filing fees are high ($5k+ over 6 years), as is the cost in lawyers (probably similar), auditing, and time consumption. It is impossible to keep an employee on H1-B indefinitely, so generally they will also go through the Green Card process, which is also expensive and time consuming.

Generally companies will offer a relocation package, which is also very expensive when it's international, and have partnerships with banks (having zero US credit sucks) and other services to get employees settled.

The idea that hiring an H1-B is a cost-saver is utterly bunk, and needs to stop spreading. (Other than fraud)