What would you do as a side hustle if you had £200 to start it?

Personally, I'd invest it or at least talk to your bank. If you have no investments, you should start them. The earlier you put that spare income in, the better payoff you'll have when you're older. And I know that doesn't sound attractive. I get it. It didn't to me. But I started in my mid 20s and wish I had started earlier. That money will grow over time and give you a nice payout when you're older (as long as you keep putting something in). Or at the very least, go into your bank and ask to meet with an advisor (You may need to book a few days ahead). Ask them what the best way to set up your accounts would be. I needed a few hundred to set up a few accounts that basically moved money about every month and makes me a good chunk of extra interest for no work. For 20 mins in a meeting 5 years ago, I've made literal thousands for no work.