Lowered head/neck and ears pinned to neck

Okay so I test-rode a beautiful paint/qtr cross gelding 16.1 hh who was advertised as "beginner friendly..packer, takes care of rider over fences, gentle puppy dog, loves to please and work, etc".
Owner dropped him off and stated he is on the slow side and to use a crop or spurs. My trainer got on him and had to really use spurs to get him going then he would break consistently on her while trotting and canter. Then I got on him and she gave me her spurs and had my crop. He walked very slow then had to use spurs and the barely trotted then broke, then used crop, he got slower then he just stopped. THEN, as I tried to get him going, he just lowered his head more til it was lower than shoulders with ears pinned back against neck and refused to budge. How close was I to getting tossed over his head into the fence? Was this an obvious sign of aggression and anger? And, how can a "beginner friendly" horse be beginner friendly if he gets into this aggressive stance with a rider? I got owner to pick him up right away and take him back and my trainer was not at all happy about situation. Just want to know if anyone else had this situation on a horse and what happened next? Did you get tossed or is there a way to smooth things over or why do horses do this?

My paint mare gets this stance when I lead her.
I think its just because she doesnt enjoy whats happening .
To take her for a walk in hand she lowers her head right to the ground and pins her ears flat, yet this is the only time she has done it. If I am to start "working" here on ground ie. Showmanship patterns she's fine, she also seems very happy and willing to please when im on her back.
Your horse may have just not enjoyed the work asked of him perhaps?

It sounds like you pretty close to a wreck of some kind. The poor thing is probably sore. That's why you wanted to try him before you bought him. Be glad that all you spent was a little of your time.

All that behavior is a horse who is very introverted. He doesn't see the point in doing what the rider is telling him to do because he is being forced to do it with spurs and crops.....force does not work, especially with this kind of horse. He needs to see a PURPOSE. Him simply refusing to move is CLASSIC behavior for an introverted horse.

What you need to do is ditch the crop and spurs (yes, ditch them!) and go back to basics. Get him sensitive to your legs and make things FUN! Use food as motivation, do TONS of point to point exercises using grazing spots. Are you familiar with that exercise?

She doesn't own the horse.

But if she ends up buying him, that is what I suggest ;)

I sure wouldn't buy him cause that could be from a myriad of problems. He could be sore somewhere and it is uncomfortable for him to move, or spurs and crops have been overused and he has become sour from them. If they encourage everyone to ride him with spurs or crop, 99% of people don't know how to use them properly. I am willing to be that instead of using these tools as refined cues, they were using them as standard cues and many people are just too darn harsh with whatever cues they use. There may be a nice horse in there somewhere but it would take a lot of work to get him there.

I think it was extremely wise of you to return him. That would have ended very nasty.....

I think he must have been in some sort of pain, or maybe in the past he got away with things by doing that, and now it is a very bad habit that has been ensured.

I think you did the right thing in returning the horse, he sounds like he is in pain or he was let do these things all his life and has learnt that if he does this the pain/work will stop and he gets to go back to eating

I personally don't think you should discount him altogether. These issues are easily fixed with the right approach and a ton of patience. It's not an issue that can't be ressolved.