I suggest that you donate the higher quality instruments to the band department at your local school. Quality instruments can be quite expensive and many students would find them difficult to afford. I'm sure that they would be well-used and very much appreciated... especially with the tight school budgets these days. You could donate the lower quaulity instruments to an elementary school.
Concerning the maps.... I recall a man that died a few years ago in Sacramento. He collected maps for much of his life. He had thousands of them in his home. Some were simple travel maps while others were very old and expensive antique maps. I believe that the Sacramento public library was invited to catalog all of the maps and take all those that they wanted for the library collection. The people at the library were thrilled to get such a collection. Of course, you could also do this with your collection of books.
So, what do I own? Notably, a tremendous amount of gaming stuff -- role-playing books Ive used, a greater number Ive only read through once, board games Ive played and those with the counters still unpunched. And maps. And little monster figures. And dice. The whole collection takes up 25 shelves.
And about three dozen musical instruments, not counting plastic recorders, penny whistles, harmonicas, stuff like that. And a dozen shelves of sheet music.
Books. Thousands of books: art noveau, science fiction, boy scout manuals, a dozen books just on the cups-and-balls magic trick alone, math texts. Religious and philosophical books. Star Trek bloopers. Exactly one shelf of cook books.
I own other stuff too. A car. Kitchenware. A computer. Cheap furniture. Renaissance garb. A mysterious collection of hotel shampoo. Down in St. Louis, I own 40 YEARS of superhero comic books, starting with Marvel in 1974 and including DC a year later.
I have no heirs, per se. My family loves me, but they have absolutely no interest in any, any, any of this, except maybe the computer. No other living person born with my last name plays music, or enjoys playing board games in any way. Or reads books, for that matter.
It's a question of stewardship. What should I do, to get this stuff to people who would put it to good use? (Or should I just instruct my executors to auction everything off?)