1. Does your muse collect anything? For the fun of it or for material gain later?
Guitars, almost exclusively electric. He has one 10 string just for shits, the rest of them are 8, 7, 4 strings. It's the first instrument he learned how to play so it's sentimental and for fun
2. Is your muse materialistic?
VERY. He didn't grow up with much so now that he has a fuckton of money he spends as much as he can without being downright irresponsible with it. He doesn't care much about quantity of something(unless its the above), more so quality and rarity.
3. Name one thing they always wanted to have but either couldn’t find or couldn’t afford. Would they steal it if they could get away with it?
I actually don't know what specific item, I'd need to think more about that one, but no matter what it was he would steal it no doubt about it.
4. Have they ever hurt someone by taking something that other person needed? Did your muse need the item too or just want it?
No, and he wouldn't either if it's actually something they needed. Again with the whole growing up in a basement venue thing, he knows what it's like to truly need something and how shitty that was. He normally wouldn't give a shit, he's a very "As long as it's not me" but anything that reminds him of his childhood too much gets him.
5. Have they ever stolen something directly?
His first guitar was one he stole so yes, but that wasn't the first or last time he did steal.
6. Name something they have too much of. Have they tried to get rid of it?If no, why?
Aside from what he collects(which he will never get rid of for the sentimental reason), Clothes. Most of it is just PR. What he doesn't cut up or modify in some way he'll give to a band mate or send a girl home wearing a shirt if they weren't wearing much and he's feeling courteous.
7. What would they do with a billion dollars or the equivalent in their world?
Probably spend it on a fucking mansion and a just for shits a couple of famous original paintings because he can. He’d just keep the rest because money = power(AKA holy shit i cannot conceptualize this amount of money to give a Really In Depth Answer)