Getting a bunch of 10 baht coins (change for laundry)

Does anyone know good places to get change (10 baht coins) in Chiang Mai? In Bangkok, banks didn't keep coins. I solved the problem by getting 10 --> 10 baht coins for a 100 baht bill whenever I went on the BTS, even though I had a Rabbit Card. I soon had a bowl of 100 - 200 10 baht coins for the washer and dryer. My apartment office doesn't have change and the 20 baht bill reader doesn't work.

Thanks.

Good morning!

Why not just use a laundry service and save yourself time ... and “coin collecting?”

Many places offer pickup and delivery (often for free), and prices seem to be 40-50B/kilo for washing, drying and folding.