Trying to tailor to 2 subjects!

I haven't totally decided if I want to do Business or Social Science at university, how difficult would it be to write a personal statement that covers both? Any advice would be helpful!

The best advice you'll get is don't apply until you have decided what you really want. Putting both in one statement makes you look either uncommitted or ignorant of what the course is about, and neither of those will help you get an offer. Decide first, then make a proper job of the application.

I thought I would be able to get away with it as I was going to talk about business through my extra curriculers and then social science through my high school subject choice and interest in politics ect.

I know that social science would interest be more but I am hesitant about the jobs available after it!

Don't talk about your school subjects. Everyone who studies them studies the same content - it doesn't tell the university anything about you personally. In addition, you have given these subjects up, so why are you talking about them when the space is better used in talking about the course you want to do?

Well my school subjects all fit within the social science degree, and as does business as there is a business module in the social science degree so I'm sure they would consider this?