I've not counted the car, because I need to get to work and back.
Helis once the initial outlay for a decent indoor birdy say £120-150 the only spend is the odd spare part amd batteries
Scuba is a bit different, actual outlay for gear used all the time is about £250 I've not bought a wet suit yet so add £250 for a decent wet suit another £300 for a bcd, that's about £1300 for a full kit add another £100 for a 20m dive camera that gets to £1400.
I've only bought the Fins, mask, boots, snorkel and camera so far about £350 worth, the rest is planned this year
I forgot it's about £300 to get qualified as an open water diver
The next expensive bit, the holiday some place warm to dive, being a coward I'm not diving in the uk too boody cold
So average per year about £500 - £1500 a year