We have exhaust extraction, it was second hand when we bought it and installed it about 15 years ago.
Ours is a permanent fixed roof mounted system with chimney and 3 extraction hoses.
From memory it cost about £1500.00 installed.
It works really well, so long as you keep the filters changed regularly.
The biggest problem is making sure everybody uses it all the time, as they think it takes to long to put the hose on the exhaust and start the extractor up but as from other posts, its not just there health they are messing with.
Andy