Hello Matt, I am new to the board myself and am looking forward to the many different ideas and tips from all the members here. Just a thought about the dimensions of your new hangout. I am not sure how many stalls or spaces you will have or how you will arrange them, but take into consideration the size of the vehicle with doors open and walk around space between the doors and workbenches, storage on side, etc. I would figure on about 18-20' width for each. This will enable you to park a vehicle in it with the vehicle doors open and still have room to walk around when working on it. The shop that I built several years ago has two 18' wide stalls and it works pretty well, although with storage or workbenches along the walls, it could have been wider. Also, dont forget that you will lose a little of that dimensional space due to the wall or purlin thickness as most building sizes are based on outside dimensions. Apply the same logic to the depth of building.
With the addition of a vehicle lift, the height may vary, so be sure to check the specs on the lift that you are looking at. Also, the concrete slab will need reinforcment at area of lift attachment or at least meet a minimum thickness and hardness, I believe. That info is available from the Lift manufacturer.
I agree with Falcon67 that more room is better, trust us.
Hope that your prescribed treatment works for your addiction!