Ticket Reselling - Potential Profit Margins

I'm going through BUDs right now and only have weekend off, given I don't have much time or energy, I thought (concert) ticket reselling might be worth a try.

I just wanted to ask if anyone has done it, the potential margins of profit, the does and don'ts and any tips would be greatly appreciated.

If anyone has any other side hustle ideas that would be as easy and as passive as this one, I'm all ears.