Of course you're not nuts for starting a project at your age. A great deal of the enjoyment is the building process itself. Even if you were only to get it partailly finished and pass it onto another builder, no big deal. You did your part in saving it and probably had a lot of enjoyable afternoons in ther garage to boot. As far as money? Well, if you dont spend it here you'll likely spend it somewhere else and since you cant take it with you anyway, what the hell? I guarantee we all spend money on things a lot more frivilous that this. Jump in, take one task at a time and enjoy each small victory. And if you do happen to throw in the towel later down the road, give me a call.