If you are really uncomfortable with assembling it yourself.
Or if you want a warranty.
Getting someone else to assemble it is an option.

There are available resources online, for assembling a system.
It is not that hard to do, although I believe making instant soup is a bit easier.
(Quoting someone, who said assembling computer parts is easier then the soup).

Going with a store, and they'll charge you $50 to $200 for the assembly.
The warranty will cost extra too, set at a rate where the store comes out ahead.

On a budget, I'd either build it myself.
Or find a friend who is comfortable building a system and supply pizza and beer.