What should I do?!?

I have been suspecting him for stealing various things like my watch, phone charger, money from my wallet that I left in his car, and now, money from my house. He slept over last night and in the morning I was in the living room and heard him at the counter in the kitchen, I peaked over there and saw him taking quarters out of a jar. When I went over there they were already in his pocket, and he wanted to buy a tin of chewing tobacco. He said he had 3 dollars and he needs one more for it but he thinks he has quarters in his car. I suspected he would just use the ones in his pocket. That shows me that instead of asking me for a dollar that I would've gladly given him, he would steal it from me. He always has amazing excuses when asked about something he did wrong almost like he thought about it in advance. But this is the first time I have actually caught him. I haven't told him that I saw it yet but idk what to do. This makes me sure that he also stole those things listed above. WHAT SHOULD I DO? he is/was a great friend. I don't want to fight him (I could easily win). I want my stuff back. I don't want to lose this friendship but it looks like ill have to. he is also teaching my brother guitar which poses a problem.