To the OP's question. Yes you are looking at it wrong. In your price list you have gone for mid quality parts. The "deal" machine is full of old in appears in some cases if not all obsolete and cheap, it would be OK maybe for SAT TV but I would be very surprised if it could pay Freeview|HD at anything better then terribly (of course not with the software it comes with). Do you really think the case is going to be equivalent to a $400 Antec Fusion case?? Basically it is old stock that someone is just trying to get rid of in a hurry while some people might think it has some value.
As has been pointed out for not very much more money it would be possible to get something that would really work but if you wanted a good quality setup that will work for some time to come then yes you would have to spend quite a bit more.