DD, when you find that spot to build a garage on, a few suggestions "before you build":
1- "plan, plan, and then plan more". Think like you would if you 25-30 years older = so much easier to play when you have room and, most importantly, don't have to roll under to see what you need, roll out, up & down (way too many times) to get tools and finally (after your knees, back, shoulders & etc. have told you "it is way past time to stop) you either completed the task, or selected a "I'll get back to it" time. Trust me on this, I know...
2- don't settle for what could be described as a "two car" - they're really just not big enough. Oh, they might "fit" 2 cars but try working on one with the other "if you're lucky" 4' away. Think about; space for a workbench, tool boxes, compressor, hang out with car buddies and just talk.
3- metal buildings are inexpensive and long standing with many size variants available.
4- think "I have 1 car now", but that is a slippery slope - you always see "that one" that you desire and if you have no room for it...
5- if you "truly" feel, you'll "maybe, only" end up with 2 cars, use the following as a "guide". You'll have the one you drive "occasionally" and the other "cherished" one that'll get less road-time than the other. Select a 4 car building, include room on one side with a shed roof (you never know when you might find another of "the ones". Give ample room between cars = about 8-10' as well as at least 6-8' on each side. Get 10' high doors and at least 8' between them on the exterior. Plan for; 150-200 amp electric (compressor, lightning, lift, refrigerator, entertainment & etc.), plumbing - yes = hot & cold, toilet (make a closet in a corner - nothing sucks more than being "into the groove" and having to stop "just to go", remember if you have to "go" in the house you have to clean up first, then when you get in someone will always need something. We're talking ½ hour interruption here... Insulate, heat & cool - you need to not be freezing or dying from the heat - plus you can work "year-round" and "any time you want".
The above are some "basics", really. Do it now, while you are young and can afford to. If you think you can't afford to now, think how you "won't" be able to after kids are thru college, married and grandchildren come along.
Just my 63 year old didn't do it 20-25 years ago self sharing "what I wished I had done".
Enjoy life for it certainly flies by too soon.