I'm going to post an experience I've had recently with a collection agency in the hopes that it will help someone else avoid this in the future.
Recently, my husband was hospitalized and we were presented with a sizable medical bill. We were able to pay most of it, but a portion was turned over to a collection agency. I contacted the agency and asked if we could make payments. They said that yes, we could, but offered a lower amount if we were able to settle immediately.