We've used family cloth and cloth wipes for about five years. I've successfully converted dh and my 8yo. The rest of the family has the option to use tp or cloth. (Have you ever tried to forcibly convert a 17yo boy to family cloth?!) Our friends make fun of us and call themselves environmentalists while they use paper towels, foam plates, and dozens of rolls of tp! Seriously, when we have white elephant gifts, I invariably get a package of wash cloths - hahahaha, everyone laughs. Um, I don't because I love it! And we use them in the bathroom! Suckers!
Anyway, I buy the cheap, large packages of washcloths from WM or Target. They've lasted a good, long time and I don't have to sew (win/win). We have probably 5 dozen in circulation for dipe wipes, family cloth, and mama cloth.
TBH, I don't waste my time with baby washcloths. I find the larger ones much more useful and efficient. My dd uses baby washclothes and squares of fabric, but I like to wipe/fold and use only one cloth. Plus, I am totally anal about how they fold up neatly in the cabinet.