When we first purchased our farm my kids were much younger and I did not have the time to run a full service boarding operation. I had several people wanting to keep their horses here and so I decided I would try a "co-op". I ended it after 8 months. The main problems that kept arising were: 1. Despite detailed check lists, people did not complete all the required daily chores nor did they do the work in the manner in which it was agreed upon. ie - quality of box cleaning, forgetting to clean waterers, etc. etc. They wanted to do it as quickly as possible and get "their turn" over with 2. There were inconsistencies in the people doing the work. In one situation the boarder would send her adolescent children to do her work when she did not want to. 3. There were inconsistencies in the methods by which the horses were handled. ie - an orderly versus disasterous brinigng in of the horse group, improper amounts of food being fed, halters left on...the list goes on.
I would also find open gates, fencing electricity off, lights left on, tack room unlocked. I was really disapppointed as I felt it would be a great way to save money and time for the parties involved. However, it just was just too much and the meager amount I received for the base rent was not enough to cover my worries and what I felt was not the ideal care situation that I wanted for the horses. So, I quit having horses, except ours and one other person for a four year period until I was able to do it my way.
I did talk with another horse owner who was in a co-op with three others and she relayed some of the same on-going problems but felt the savings for her was worth it.