Trogdor, I think you should read the section called "Attunement" on pages 136 and 138 in the DM Guide under the larger heading "Magic Items" which begins on page 135. According to these guidelines, "Some magic items require a creature to form a bond with them before their magical properties can be used. This bond is called attunement....[page138] a creature can be attuned to no more than three magic items at a time." I'm not sure which, if any, of the magic items each character has in this game require attunement (if any), but it's something to think about with regard to planning for future magic items.
Of course, the book is rife with reminders that the world and the game belong to the DM, and he/she is free to mold the rules to suit the game desired by the participants. I simply point these things out for informational purposes, because, hey, knowledge is power.