One observation about learning to fly choppers is that you will own at least two. The one you learn to fly and the one you wind up flying.

I don't think it's possible to learn without trashing the first one, many times. They are a bit like cars in a way, once the frame is tweaked, they just don't drive right. You can learn to compensate for it, but it's not the same as flying one that never been bent.

As to which one, it needs to be one for which you can readly get spare parts. It helps a lot if the local hobby shop is into it and keeps a ready supply of the commonly damaged parts on hand.

Building: This is where you can help your self a lot. Making sure everything goes together squarely, is not warped, is well balanced, and that all moving parts work evenly and smoothly will help a lot. Make sure all the linkages that should be equal length are actually equal. A set of dial or digital calipers can help with that. For instance a 90 belcrank that is not square to the linkages when it's in the neutral position will generate unequal throughs.
Basically be meticlulous.

The simulator will help a lot. Early in my learning I had done a series of up forward a few feet stop rotate and return. I finally worked enough nerve up to try to reverse course without first halting. I was completly shocked (shouldnt' have been) when after using the tail rotor to spin the chopper 180 deg. that it kept going away from me. Tail first no less. Don't expect your chopper to match the moves of the one on screen. the dynamics will be far different.

Stable hovering is an advanced skill. You will have a lot more fun if you can get someone to teach you how to get off the ground and into forward flight, then back to the ground in one peice.

Oh yes, having an experienced mentor is important. WIth determination and a deep pocket you can learn by yourself. A good mentor will help by inspecting and test flying your new chopper. Nomatter how careful your build, adjustments will have to be made. A novice just can't recognize the difference between the problems that can be adjusted away and those that just require practice to master. Better to learn flying on a bird that's been sqared away by an experienced flyer.