Tomy31.

1. I don't think so.
2. No you won't lose anything, you will get everything back.
3. You can't do that, they appere when they are one unite skill point away from 6 stars.
4. You can do that only if you are on the same server and if the player don't have more then 5 stars. Just click on the player and in the right corner you will see the option to make him an offer.