It looks like a lot to buy a used saddle from EBay or a Facebook group. The seller does not have to pay a 25 percent + fee to a tack store, and the buyer can search thousands of saddles online to find the perfect one for much less than they market new ones. But say your financial plan doesn't allow a brand new saddle–or you're living in the middle of nowhere, and you won't be able to easily pick up and return used saddles for sale back and forth to the shop. Buying online can work–but what you don't pay in price, you're going to make up for in the time you're researching and equitack is the ideal place for that.
Learn a little about fitting the saddle
If you can't discern much about saddle fit, refer with someone who does — an inappropriately fitting saddle can be sore for your horse, making you at best a lawn dart, or at worst a long-term lay-up and rehabilitation. You definitely want someone on your side that can see fit problems you may not be able to do–but it certainly doesn't hurt educating yourself. My favorite resources are videos from YouTube. They're short, simple, and you can easily see what they're trying to show you.
Check as many saddles as possible
Even if they're not the precise type you're looking for borrowing saddles from your coach or friends to see how diverse saddle brands fit your horse, they can help you figure out what your needs are and what you want. On a basic level, you want to figure out what kind of saddle you want as well as the size of the tree and seat you and your horse require. Hopefully you'll also start to figure out what features and brands you prefer from trying out several different saddles. Keep in mind, however, that the fit can differ depending on the age and make of the saddle, even if it is the same brand.