I have a few. Mostly DIY for the cars. Sure, I'd like a Vyper or similar. Just takes more space in my situation.
My goto is a Craftsman 4 leg/wheeled. 15? years old. It's a rebranded Whiteside. Reasonable lightweight. Durable. The seat extremely durable. Very good stability. Has magnetic strip in the tray. I've added a few more. Due to the low tech wheels, brakes are not really required. Not entirely a smooth roller. Sitting and rolling is limited. Somewhat implicit in it's design. Maybe a rear handle upgrade for picking it up.
Folding plastic step stool. $10? The local PDR guy had to resolve some dents. He uses his for short work. I've assimilated for short work.
Don't knock it. It does have it's value. And can go just about anywhere. No rolling, and no storage.
Hydraulic Whiteside. It's more for work that requires some height adjustment or just some extra height. Primarily used for detailing. As others have noted, it is hydraulic. It will fail eventually. Mine is still working and I've got my value out of it.
The medical screw stool listed above is a great idea.
If you believe you are planning on sitting a lot, factor in comfort. Either by purchase or modification.
Rear seat back (depending on chair) has the advantage of using some **** movement to move it backwards as you stand.