Wow... You aren't asking for a miracle or anything are you?
Even shopping Behringer, or Kustom, you just aren't going to get there, even used, at the price tag you are wanting to get at...
Assuming just for vocals, 4 vocalists. You would need 4 mics, 4 stands. To keep it on the cheap, the lowest cost, usable mic I am aware of is the Nady SP-5, you can get a single mic for $15.00, a package of 3 for $29.99, so let's just round and say for $45.00 you have mics.
Lowest cost XLR mic cable I am aware of is the CBI MLC20 20 foot mic cable at $6.09 each, you need for so there's $24.36
Mic stands. Again shooting for lowest cost period. Samson MK-10. Thankfully these are decent stands on the cheap, they go for $19.99 for a total of $79.96 for the 4 stands.
And you need a mixer to connect it all up, minimum of 4 XLR inputs. lowest cost, no frills I am aware of is the Behringer XENYX 1202 at $89.99
At this point you have already blown over your $200.00 budget, and you haven't included powered speakers, speaker / power cables, or stands.
I am pretty sure you aren't even going to get there shopping used.