Join Date: Aug 2008
Location: Canberra, Australia
There is no reason that you can't back one of them. How older is this mare? If she is a lot older in might be harder to train her, and maybe not worth it, either that or she is probably broken. A lot of it will depend on the soundness of both of them. If I was you I would go there and look at them, evaluate how good they are with people, if they look physically okay to start training maybe pick one and start taking out too feed it, give it some brushing. Once its reasonably used to you take it for little walks around. In the first few days you will get an idea of how much handling they have had. Like how well they respond to the lead, if they instinctively turn round a gate, or yield a little when you lean on them.
As far as teaching to lunge, if the horse is calm a corner of a paddock should be fine but if you maybe be better of lunging with a bridle and definitely gloves. I imagine you would know pretty soon if they have done it before. Otherwise start of on a shorter rein and work out, so you have control.
Long reining - I would be hesitant. A lot of people do it, but a lot of people screw it up. Things can go very wrong if you don't know what you are doing. Practice on a trained horse first. I don't long rein, but its something to think on.
Keep going as long as the horse is okay. Once you know them you should know that they are ready to go further or if their not. Use your judgment.
Have fun with it though, and don't try to rush.