I would say cobble a system together, if you have the time, the diy skills and the inclination.
otherwise just buy one.
i'm really happy with my cobbled system.
for about £2200 I have a 525 litre capacity (in a scudo), on-board merlin, hot water, an everyday 21ft x-tel (might upgrade to an slx in the future), a 42ft emporium carbon fibre pole and 100m minibore hose reel.
did I mention that i'm really happy with it?