Which is the better, custom built shed or buying a storage shed kit?

I was wondering which way to go to save a little extra cash. I want to add some additional storage to my backyard and was considering a 10x10 or 10x12 storage shed. I really like wood siding since it is easily customized to match surrounding landscape.

I might consider going with a vinyl or steel shed if the quality is good and the price even better. I've heard that wood sheds are pricey not to mention yearly upkeep. Vinyl would work if there are more choices than standard egg shell white.

I recently priced the shed plan/materials for wood shed built and was surprised by the high material cost. Not to mention paying labor. My co-worker mentioned metal storage shed kits and said they are well built and just a fraction of the cost of wood and vinyl.

My question is "will contractors assemble these shed kits for homeowners"? How much should I expect to pay for a medium/large storage shed...i.e 10x12?

I was thinking around $300.00 was fair. This does not include any foundation work etc. The shed will sit on an existing concrete slab on my property.

How about the quality of the many storage shed kits for sale on the market. Can anybody recommend a brand name? I noticed Home Depot and Lowes carries the Arrow and Handy Home Shed models, but these are pricey.

I searched online for storage sheds for sale and found a few dealers there. I am leaning more towards the Arrow or Duramax brand shed kits, but any advice would be much appreciated.

Also, what should I expect to pay for a standard gambrel barn design shed in wood for materials/labor...whats a fair price?

Thanks!