I suppose if you had the space you could spend 2-3000 on a good rack and weight setup on Interest Free Credit. Might work out about 50 quid a month but its similar to a gym membership and you get to keep the goods
home gyms are more expensive, there is no way you can get the same amount of equipment on offer at a "proper" gym and it work out cheaper.
i'll give you a list of some stuff i want even though i have like over £3K's worth of equipment.
GHR or Roman Chair - £300 minimum
Concept 2 Rower - £1K minimum
Tricep Bar - £40
Shrug Bar - £180
Leverage Chin and Dip - £600
that's just some of the stuff im looking to add over the next few years, plus where are you going to store it all? i still would not have access to a treadmill, swimming pool, sauna, steam room, etc.
also this company has the best custom made stuff in the UK
http://www.gymequipment.uk.com/ i think gymratz get their stuff from the same guy, but they are both extremely expensive. i would love to have their leg press which is like over £2,650 on its own excluding shipping.
http://www.gymequipment.uk.com/store/item/38hav/Plate_Load/Animal_Leg_Press.html
what a machine.
you can however if you do not want a lot of variety make a really good home gym with £1-3K. which in essence would work out a lot cheaper than a gym membership so long as you used it often for many years, but you would be stuck with the basics so to speak.
a simple thing like rubber matting is expensive, never mind the equipment, but some people prefer to train at home, like myself. the gym i used to go to was a half an hours drive away (one way) then add in the cost of fuel as well as time wasted, i thought might as well just build a home gym, i never thought it would cost so much, i thought £1.5K and I will be done, but then I needed proper dumbells, another £1K.
i dont care now how much it will end up costing, it's there forever, my brother can use it, as can my dad, as can my future wife/kids. i may even decide to open a commercial gym in future, you never know, it is a possibility i have been considering.