… And next time, bring your keys with you, even if it is in a foreign country.

Yake them to a small claims court if they refuse to pay for everything. Hell file a police report saying that he stole the keys and tried to steal your car. And your mother is an accessory to Grand Theft Auto.

Wow, she had no right to tell your brother that he could use anything of yours. And since you said your house, I assume you're living on your own, which makes her have even less authority over that kind of thing. You shouldn't have to make your brother feel better for crashing YOUR car when he shouldn't have been in it to begin with. Your mother has her priorities wrong.

That's why when you leave you hide your keys

That is beyond normal frustration with family and into mentally abusive and criminal territory. That is a huge overstepping of boundaries and you need to set a firm line now that this is NOT okay, this is NOT your fault, and you will NOT be browbeaten about it. Otherwise things will get worse, and you will never be made whole as your family will think it is "your fault" forever. And will continue to destroy your things because you didn't make it clear that they will nto get away with it. Get your mom to sign a written statement detailing exactly what happened, including a promisary note to pay back every goddamn penny. Make it clear that SHE gave your brother permission to use YOUR property, without YOUR consent, damaging YOUR property. Make it clear that if said note is not signed, police will be involved. Make it clear that if money is not paid, lawyers will be involved - assuming damage is under the small claims court limit, that is a cheap way to get results.

Today on "Things that didn't happen"..... It's your house? Your car? Your Mum can decide to let your sibling go to your house and drive your car. Sure. Why do they have keys to your house and car if they're that idiotic?