I've owned a number of doubles. Mine have all been 9.3 or smaller and under $10,000. So no expert with the bigger bores or more expensive guns. Try to get together to a double rifle shoot and shoot a couple different guns. Short of that, go to some shops and shows and at least handle some. For the investment it will be time well spent.
Think about how you hope to use it. Dangerous game only, or mixed bag hunting, open sights or scoped or mixed.
I have decided that fit is critical. My current Chapuis fit me perfectly until I had some serious body repairs over the last two years. I've lost significant length of pull and whatever you call the space from your palm to the joint in your trigger finger. Now it is difficult for me to shoot it at all, let alone well, and the wood is just too ni kikce for me to chop it off and make it useless to anybody with a normal length of pull. So I'll probably be need to say goodbye to that one.
Single trigger or double trigger? Doubles are the classic, but i don't shoot them well, so I prefer single triggers. I like ejectors, others extractors. Old English or German, vs new? Lots of arguments for both.
If anything needs repaired on a double, you will need to allow time for repairs. Project doubles are like a free dog, expensive.
Doubles are fascinating and fun. Like bolt guns there are endless arguments about the perfect one. None of those arguments is all right or all wrong, just wonderful differences of opinion.
Just a few thoughts
Bfly
