Call any building supply store and tell them you want to build a 24x24 garage and they will give you a quote. Not difficult at all. Simple as one or three phone calls. More on reddit.com

I built a 24x24 garage last year in a major Midwest city. Used 50% of an existing pad, and poured a new pad for the rest. I framed the walls with 2x4 @16" O.C. and put scissor trusses with an 8/12 pitch at 24" O.C. Cost was about $21k (not including the concrete work) which included a 100A sub panel, all finished electrical, and the digging of a trench to the house. More on reddit.com

Found a concrete guy did my pad for $5000. I had my house framers come out and frame up a 28x28 10/12 with a loft on top $4000. Hired some fellas to do smart siding and metal roof for $1200. The total came out about $25k including materials. Be your own contractor and hire subs. Otherwise you’ll pay. Location is NW Indiana. 30 mins from Chicago. More on reddit.com

So I’ve done some research on those size garages and am in NJ, not too far. As for taxes and what you can build, you need to check with your local zoning board. I’ve reached out to a ton of the PA Amish builders and can give you some ball park estimates I received. Pole barn - 24x 32 x 10 - this would have cost me about $26k all in with 4 inch concrete. Pole barn - 24x24 with a second floor (fully walkable) - this one I had up to around $45k with windows, doors, 4 inch concrete, and a small lean-to.  Now for the Amish garages: Generally, I found the excavation work they offer ranged from $12.5 - $15k for a 24x24 or 24x28 garage. I wanted the garage built on site, with a second floor. If you’re pouring a full slab, you will want the garage build on site, meaning no wood floor.   For the structure alone, depending on your options, it can get crazy. A 24x24 mega garage from my sheds was around $55k, that’s with a fully walkable 2nd floor.  Most other quotes with a second floor were similar in cost. This does not include any electric or plumbing. Just a building with some doors and windows. So realistically your building + concrete will be around $70k if you want 2 stories.  A true stick build was priced at over 100k for me. I have since stopped shopping- I need to take a step back and determine exactly what I want if I am going to pay nearly $100k for a garage. Edit: you can get away with a 2nd floor for cheaper if you want it to be less functional. Just an FYI. More on reddit.com