Could you tell if someone was just trying to fill a training spot for the money and not because your horse is really that good? How would one be able to determine the motives of a trainer/handler? Are there specific things to ask or look for?
Great questions and there aren't any easy answers I don't think. But here's some of what I look for or shy away from and also some of the things that've been said to me that turned me off.
If you don't like my horse, go ahead and tell me. But do it in way that educates me. Point out what flaws you see and spend a few minutes explaining it to me/helping me to see it too.
Don't over promise things to me. There is NO way a trainer can guarantee a win unless they are bribing a judge, so don't insult my intelligence by doing that.
Don't take my horse as a "back up" for one you already have in the barn in the same class. Or at least tell me that's what you're doing.
Explain to me, up front, how it's going to work when the trainer has multiple horses going back into the grand class.
Don't tell me you'll take my horse sight unseen, because then I know you're just in it for the money and care nothing about the actual quality of my horse. Also don't tell me you know my horse will do well as a senior horse just because they did as a junior horse. NOT always true. If you just tell me that, you're probably just out for my money.
I also would run as fast as I could from a trainer that said or did anything to indicate that my horse would be forced or scared into doing anything. I can't tell you how many horses I see waiting for a class to start that are completely terrified of the person at the end of the lead. I may back my horse up a bit or do something to get its attention before we walk in the gate, but my horse in never terrified of me. Never.
Hiring a trainer for the first time is never easy. Trust your gut, ask around, ask for references, do look ups on the net, find people (other than the references they give you) that have used them and find out why they no longer do, go to shows and WATCH the trainers you are considering.