Welding Tips and Tricks

I've had several people approach me looking to get metal laser cut.

I've been looking at larger bed lasers, and am familiar with cutting plastic, wood, textiles, etc. but I'm not sure what the next step up is to cut metal.

Has anybody done this on a smaller (non-industrial production) scale? What's the best way to be able to offer this as a service? Do I need to source a fiber laser, or can I run O2 through a lower power or CO2 laser? What kind of results can I expect at 1/4" steel? Is 1/2" possible?

I don’t know much about power levels. But I do know metal lasers I’ve been around all use o2 and nitrogen.