To cut a long story very short, the campaign's opening story ends with the following: The party's mentor, master and "step-father", a level 18 neutral evil wizard who dabbled in shadow magic, is dead, and the members of the party are his heirs. I know what the wizard had on his person - but he has a fortified house in a nearby city, with a well equipped lab and a rich library. The party has access to this house, and I'm not going to rob them of it completely.
Without rereading half the DMG and other books: How could I quickly come up with a relevant (and not totally random) inheritance/treasure that makes sense? And what do I let a level 4 party keep from it, and how do I take away the rest, or at least limit their access?
I know it's not your regular way of acquiring treasure and so on, but 1) story and its relative credibility has always been a priority for us, 2) I haven't DMed DnD for a long, long while, and yet 3) I do not have too much time to prepare, unfortunately. So, I need a quick and dirty method that produces plausible results, nonetheless.
(Are there semi-random treasure generators out there, perhaps?)