Having just been through this process (about a year and a half ago) I think I can speak to this.
Start with
Redfin. Create an account. Learn how to use it to its fullest. Don't wait for your realtor to feed you listings, go out and find them for yourself and use the realtor to get you into the places you find.
In particular, take full advantage of the built-in map view in Redfin, or copy the address into Google maps and take a peek at the property with satellite view. If you're lucky, you can look at a 45° angle from all four sides of the property, depending on the area you're looking at. Keep an eye out for outbuildings. Find the back wall of the garage and figure out if it's open to the back yard (future expansion) or if there's an immovable object (like a living room) between the garage and your future workshop. Trust me here, the two-car garages you find will quickly be filled with junk. Or cars that don't need to be garaged. Same same.
Open up Redfin every day and look at the new listings. Mark the ones that don't meet your criteria (you can "cross them off your list", so to speak, within the site) and keep looking for that ideal property. Its out there, for sure. Your realtor won't be able to find it, though. That's on you.
Outbuildings are golden. Already permitted and built and accepted by the neighbors is worth a
lot. Don't plan on building a garage unless the property is
huge.
Get pre-approved. Have all your ducks in a row. Be prepared to jump at a moment's notice. Have your realtor write offers when you find the perfect property. Be prepared for heartache when you get outbid, or the selling agent jerks you around and/or doesn't accept your offer for [_fill_in_irrational_reason_here_]. Don't get too emotionally attached, because it will fracking
break you.
Avoid short sales unless you really, really like prolonged agony. They can drag on forever, and in the end your offer might get turned down. REO (bank-owned) sales are almost like a regular sale, maybe even better because the bank will be in a hurry to get through escrow.
Your mileage may vary. Offer void in Hawaii and Alaska. Professional driver on a closed course. Pigs cannot actually fly.