I would said the size of quilts. King size I would said 1. Queen and twinwould be ok. But you want them clean so better off with 1 per washer.
About 3
Depending on size-full to queen probably 3
It is a pretty big machine. I think it can handle 1, possibly 2. It all depends on how big the quilts are. The best person to ask would be the attendant the works there during the day. She is usually there by 9am and leaves at 5pm.
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