i just built mine last year and have enjoyed it every day since. i built mine as big as the city would allow and as tall as they would allow. i also put in several 220 outlets since i have several 220 machines. i wish i had put in more light and heat but i will do that down the road. i did a 5" floor throughout the whole garage and a lot of extra steel rebar, especially in the center. i don't know if i will ever get a lift but i think it could handle it.
i also built the pad 12" off the ground so i had to bring in several dump truck load of rock to fill to the right hight. i also built a shelf around the top all the way around for storage. i also got a wide overhead door and even added a extra panel for height. i say don't skimp on the basics, you can always add the other stuff later.
