Once you start to delve into the gaited world, it can get a bit confusing
. First, take an inventory of what you look for in a horse. If you've got a lot of energy, you might want a higher energy horse. If that's the case, a paso, pp or even the right trote y galope (though they are hard to find and expensive) might be up your alley.
I've found tw's to be a bit more laid back, though some come with a big motor. Some people hate the head nod and find it distracting. They also don't like what can be a "camel" type walk, lot's of back and forth, front to back in the saddle.
Ssh's and mft's can be laid back and comfy, too. Same as rmh's, kmh's, etc.
As for price, it depends on where you are. Here in my part of Florida, the rmh's are big money. It's not unusual to see a green broke gelding with some color with a price tag of 8k or more. Paso's range in price from $500 to in the million dollar range. Tw's start around $1200 and I've seen some trail horses around the 10k mark.
What it boils down to is there is NO absolute in personality and temperament when it comes to breed, just generalities. Price is all over the place...just take your time, ride alot of horses, read, read and oh, hey!! read!! and ask questions.
I've found pasos and pp's to be more naturally gaited and most are started in a nose band and as their training increases, move to a bit. Some of the bits are just as ugly as the tw's bits, imho. No special shoeing required however most of them are a bit more upright to keep a tighter gait.
Tw's, no special shoeing though you'll be told differently. If a horse needs heavy shoeing and long shanked bits, you might want to rethink the purchase. Personally, I like to see a horse that is balanced and without lot's of "gimicks" to get them to gait. All of this has just been through my experience and again, not written in stone