I would give it a shot to see if your Mom is more receptive to the idea of working with the trainer. If the closest one you know of is 45 minutes (and you know that she's good), then perhaps some time spent with her once or twice a week would be sufficient. If nothing else, she could give you some great ideas on what to work on at home and she'd be just a phone call away if you start having trouble.
Personally, I would keep him in the snaffle because that's what I use for all my initial training so that's what I'm most comfortable with but if you want to try to keep him bitless, you'll need something like a sidepull; something that gives clear direct reining cues.
A few things that you can work on in the meantime is getting him supple to the bit each way. Starting from the ground, stand at his side and take up a little pressure on the rein on that side. Keep yourself in the same position on his side and move with him if he starts turning circles. Keep that pressure on the bit until you feel him "give", which is to say that he voluntarily reaches his nose closer around toward the stirrup and takes the pressure off his own mouth. The instant that he does that, let go of all the pressure and give him a bit of praise (I'm not a fan of treats for things like this as it can make them a treat-monger, I've found that a gentle scratch on the neck works just as well as anything).
When he straightens his neck back out, let him stand there a moment and then ask again. Keep doing that over and over on each side until he willingly gives his head when you pick up the slightest pressure. Then, start again when you're in the saddle, bring one hand up to your hip bone and hold until he stops moving his feet and gives to the pressure.
Another thing to work on is getting him responsive to leg pressure. Same thing, start on the ground using a finger to get him moving his hips over and then work your way up into the saddle. Here is a decent video of how to do this correctly.
If you can control his head and his hind end, you've got control of him.
Then, you can work on something like this The Road of a Horse Trainer: Teaching "Cruise Control"
In the roundpen and get him thinking "stop". Once you're comfortable in the roundpen with all these things, you should feel a lot more comfortable out in the larger pen. When you get out there, make sure that he's still listening to you. If he's not, then work on them more until he is.
Repetition, consistency, and patience are the 3 most important things for you.