By the way, as for an indoor growing system...

How many plants are you planning to grow?
Where - in a closet? How big is the closet?
Whats the temperature of the closet in summer and winter?

For a closet, either a few CFL's/energy saver bulbs will do for a small grow - 1 or 2 plants - but ideally you want a HPS/MH setup. The bulb will cost about £15 for a 600w (400w is best for a closet though, I have a 600w HPS and mylar in a closet and the temperatures are barely manageable), the ballast will cost about £30 for a decent second hand one, and the reflector will be £15 brand new.
£60 for a decent setup (£70 including mylar) where you can get at least 3-4 ounces every few months, or spend £120 a week for an ounce? Ill go with the growing, thanks.