I agree with what Adrian and Tonedeaf said! First, you must figure out a budget, and secondly, like Tonedeaf said, listen, listen, listen on
www.archive.org and bt.etree.org mainly! Archive.org is nice because you can easily DL/Stream the recordings without fully committing to the whole DL like you would on etree.org, since that's a bit torrent site! Noone can decide which mics you prefer BUT you
And there are a lot of different samples of Schoeps/AKG omnis on archive.org! It might take a few weeks to really check most of them out, but I would rather spend a few weeks listening on there than just buying something really fast and then end up not liking it as much as you thought you would!
And another thing, like Adrian said, Its damn near impossible to find a used Littlebox/Tinybox with a Schoeps KCY or AKG Actives input in the yard sale! It was hard enough to find one when Jon WAS still making them. Now that they've been discontinued, well, it would be a matter of luck IMO
So your Schoeps options would be Schoeps capsules>Schoeps KCY/NBob KCY(I've heard the NBob Actives are easier to steal*h with since they don't have the Schoeps KCY Junction Box, and the cable is thinner and easier to manage)>Naiant PFA>+48v preamp/all-in-one recorder, which is going to be bulky IMO! Not much better with the AKG actives. Without finding a used Littlebox/Tinybox, its going to be a lot of cables and stuff to deal with IMO!
If omnis are what you're after, I would probably go with the DPA 4060/4061 omnis. They're tiny as shit, and can fit on glasses, versus mounting the bigger Schoeps/AKGs + Active cables inside of a hat! Not to mention there are TONS of samples of the DPA 406x on archive.org! And I'm sure that you can get the DPA 406x cables cut down to whatever length that you want to make steal%hing them a little easier
Hell, I like the Church Audio CA14/CA11 omnis just as much as the DPA 406x series, but that's just my opinion
And the CA14/CA11 are only $100/pair