how much would you say a good set up cost

A lot depends on what is meant by "a real good system. not over kill, just good equipment, good sound stage." The word "good" is highly subjective. Any Yamaha, Denon, Sony, Bryston, Mcintosh, B&W, Paradigm, ATC, etc. equipment will be good equipment - this is particularly true for the first three companies as their resources so outstrip the specialty companies that it costs little extra to ensure good equipment and the risk to their reputation precludes manufacturing junk.

As to the sound at all but the highest listening levels, my listening experience is that there is very little difference between a $2000 system made up of a budget CD player, monitor speakers, and a receiver (yes a reciever) and a $50,000 system. The differences are almost entirely in soundstage and accuracy and those I have found to be 99 percent dependent on the speaker. So, a good digital system can be had for $2000 a slightly better system for around $20,000. After that the returns are extremely small. But, of course, the hobby aspect tends to drive the system up but that is a different type, although very legitimate, type of return. Finally, the status aspect is completely dependent on cost, but also is a different type of return.

System Price = ego

I think it is very possible and reasonable to have a decent system for $2000-3000.

I have spent a whole lot of money in this hobby only to learn that you don't have to spend a whole lot of money to get good sound.

I had 30 k invested.. I was able to achieve far more ergonomic, better frequency response, and better performance all together after understanding more principles of the game a few years later and now having only 6,000 total invested :-)

Plus you just feel far better about yourself when you sit there starring at a couple of amps that cost you 1 fifth the cost over others that don't sound better. So it all depends on how dirty your willing to get your hands, and how many little risks your willing to take to get you there.

If you have money to burn and it makes no difference and this is not the route to take, because its a long one.

By the way I would never consider at this point from experience spending more, because I know for my personal taste it will not satisfy, this is just "Audio" its actually not that difficult nor is it anything hi tech involved quite honestly.

There is ultimately no specific cost to pinpoint this optimal performance level you seek, it will vary quite a bit from personality to person.

I will add this final note(maybe a hint) most of the big money necessary would be spent into a great room.. Those don't come cheap at all.. And can at a minimum set somebody back anywhere from 500 to 15,000...