trois, you're hilarious. "No reason why a person of that age cant work as well as attend uni. Lectures are often few and far between." It totally depends on what you're studying. Mickey mouse studies at the university of sinkhampton, then yes. A proper degree at a proper university, hell no. I'm a student in the second bracket so I should probably know.
As for financial support, if you're a low income family then you don't have to pay anything to your DC. If your income is below the threshold (cant remember what it is, sorry) then they'll get an extremely generous amount of money from the govt and you can sit back.
If they're not getting the full amount, then you can do what my parents did, which is to give me the difference between what I'm actually getting from the govt. with my parents income and what I'd get if they were on a low income.
If that's a struggle from you then give them enough money so they have £60 to £80 pounds/week spending money (after rent and transport to/from uni). More won't encourage fiscal responsibility, less will make paying bills really hard work.
IMO your child MUST NOT live at home during uni. I know you're a great parent, but uni isn't about getting a degree, it's about figuring out how to do life as an adult. If you do the washing for them whilst they're at uni, they'll half expect it for the rest of their lives. If you give them £100 as soon as they get into financial problems, they'll never learn fiscal responsibility.
I would recommend taking the full student loan, and on top of that a 0% student overdraft. Paying off the tuition fee loan so your DC aren't saddled in debt is a nice thought, but frankly impossible unless you're on a 6 figure income. Instead of paying off student debt, give your DC the money when they graduate for a car/wedding/house deposit. Student loan debt is FAR cheaper than a mortgage.