Lease Cars/Company cars yes or no?

This is a subject I get completely confused with.

Looking to replace my 4x4 early next year. Obviously its a capital outlay, so looking at all the options, and looking at revisiting lease options. I leased a car a few years ago, and at the time, the accountant advised me it was more cost effective to buy the next car myself. Didn't really understand, but nodded and agreed.

So have any of the rules changed, or does anyone else do a business lease?

Just getting a feel for what everyone else does? Do you business lease, personal lease or buy it yourself?

If you business lease, is it ok to park the car at home, as I remember being told before the car is classed as a pool car so legally should only be parked at the office.

Any company recommendations? Plus can you haggle, like when you buy a new car, or is the price set in stone?

So many questions, all very confusing