It seems a shame that you have to give up working trials. I certainly didn't train for hours and hours.

Could you get someone to make you a scale and some jumps? I had a scale at the bottom of my garden and Tess would go over and in return she would get a game of football (often with the apples that had fallen off the tree!). And the search square and sendaway are easy to set up. Apart from that it is just the usual obedience exercises. Just a few minutes 2/3 times a day with Yogi and the other dogs could join in the stays.

I found the tracking time consuming and TBH didn't do a lot. But in cd you don't have any tracking to do.

Perhaps if you start off with the cd exercises and a little bit of tracking you could expand later on when your son is older and you have more time. Or just have fun with the exercises for now because the training would come in handy for other activities later on.