building the best system I can?

I need more input.

With your budget, go with an integrated amp. You need to decide on tubes or SS. Also assume that you will want to upgrade your speakers at some point in the future.
But first tell us if you will be using a dedicated CD player or a DAC paired with streaming music or server.
If you want a CDP, there are many good finds here on Agon.

putting this system together would be sourced with a dac and cdp and music server. The use of the $5000 would be to put together a system that you could be proud of for the long term. I guess this is more of a hypothetical
question than anything else. Just thaugt it would be fun to see what you guys would do if you had $5000 to spend on audio gear. Just have fun.

Lol! I just got into all this 8 months ago and initially bought a used onkyo t..7... Something or rather and a pair of new mini monitors. It sounded good enough that I caught the bug. Since then I have bought/ upgraded quite a bit and will save you the hassle of all the upgrades. What I have now is: a used classe ssp 25 ($350), a used classe ca-150'($800), a used denon DVD 2900 ($100), a new musical fidelity v-dac II ($500 including tax and an audioquest digital coax), a new pangea p 100 upgraded external power supply for the dac ($100), two used ps audio power punch cords, one for the amp, the other for the pre-amp ($60), new 25 foot 10 gauge blue jeans cables with bananas cold welded ($105), pair of used diamond back and a pair of new g-snakes ($90 for both), and last, a pair of new studio 20's ($1500, had to pay retail as I kept upgrading and payed the difference). So not including the speakers, I have $2,100 in it. Most of it was thought out, some was bought because it just became available atthe right time, right place sort of thing. I want to still upgrade a pair of rca's, buy a pair of xlr's and two more power cords, maybe my dac later. Other than that, I'm done. This setup sounds great to me and I like it's size and simplicity. Rather than upgrade this system anymore, I'd rather just keep this the way it is and build another. Maybe vinyl with tubes?

i agree with the integrated amp route--a couple that i'm enamored of are the hk990 (which i've seen packaged with the matching cdp for <2k) and the vincent 236 (which you can find used with a matching cdp for <2k). the hk has the advantage of inboard dacs, bass management, etc. as for speakers, since your friend already has the studio 20s, i'd start with 'em, add a sub and see how it sounds. paradigm's studio sub 12 would be a logical match--i see 'em used for around a grand, though you get a vg rel or hsu for less. for a music server, i defer to others--i have a $250 squeezebox touch which which works just fine, although depending on your friend's needs there's a number (e.g. olive) which have integrated cd players, internal storage, etc. budget a few bucks for cables and wires and you'll still have some $$ left over for upgrades, room treatments, etc.