That's one of my dreams still, to build a post-and-beam house from scratch. But I'm getting older and it may well be that such ambitious projects are now out of reach for me.
Sound like fun, and you shouldn't let age stop you from doing that. Instead you should adjust your dream to building a smaller post-and-beam house. It's not back breaking work if it's a small house; our inner cave men wants to work with timber for some reason.