You'll get some good advice from the guys here generally... and IanC is right -
Most shotgun purchases are about design and function compromises... in other words, until you gather the resources to buy dedicated guns for trap, ducks, upland game, etc, you have to decide what your primary use will be, and choose which design and features fits that scenario the best, with optional capability to do the secondary things.
Keeping in mind of course, that it likely cannot do all things as well as purpose-designed units.
The most versatile shotgun out there, with excellent reliability, is still the 870 remington. Good for trap, ducks, grouse, bears, etc.
Good luck!