How about this? At the end of the scenario, the games checks to see which custom items the party has and gives the player a password which when starting a second scenario (Part 2, let's say) asks for the password. Depending on the password, the player would be given back these items.
This could also work for actions the player has commited in the first game so npc's react differently or perhaps even different events would occur in the 2nd game. Of course, this would only work for a series of games designed by the same designer.
I did this in the beginning of Adv. Club 3 by use of an interview, in a very simplified manner.
And I'm planning on using this technique more extensively in a series I am toying with in the back of my head for BoA.
