Oh and dont expect it to be on top form when you do get a horse home - As im sure you know horses are flight animals. They need to become comfortable. Piling the pressure on to work or ride is just going to heighten his senses and could lead to him perceiving danger where there is none and have lasting effects.
Whenever i meet a horse ive bought or been going to ride for a long period i start very small.
For example i rode a mare who had been broken in the year before, but only ridden by her owner. Naturally she was very nervous about having a new person on her back as she simply was not used to the situation.
I started by litteraly sitting on her back for 5 minutes. Once she stood still i gave her a little rub on her neck and got off and took her back to her field.
Next time she was happier to have me on her back. We had a walk around, which she was a little uneasy about, and again once she calmed down and did a lap of the school and then stood again for me, she got a rub on the neck and turned out.
I just gradually increased time with her as well as time on the ground not asking things of her. It took 2 weeks before i was riding her in the school comfortably and quietly with very little resistance (Obviously there was some as she was young).
I fully believe if id jumped on that horse and pushed and pushed and pushed id have ended up on my arse and the horse would have just thought 'well i dont want that on my back again'.
It is a bit rubbish when everyone else is off out schooling nad hacking etc, but the slow way is the fast way and by putting the time and building up you will create a good foundation.
It also enabled you to go back a step - For example with that mare, as we'd built up in clear steps, if we had a bit of a disaster of a schooling session and shed been a pain in the canter, then to finish on a good note i could always go back to something from earlier, a trot or a walk around on a 20 metre circle. Never finish on a bad note :)