milly - not necessarily! The loan is substantially (almost £2k) higher for students in London, and as carol says, shared rooms are much, much cheaper and quite prevalent in London - and whilst I can't imagine much worse than sharing a room, it does make a more affordable option.
dontwant, I managed uni with very little subsidising at all (also about 4hrs from home) - my parents weren't really in a position to sub me money and I got a bit of a kick out of scrimping and saving and being independent, as did lots of my friends. It wasn't easy (especially as whilst my parents were over the threshold for me to get anything but the minimum loan, I'm one of 4 kids so there wasn't a lot of spare cash at all), but I worked full-time every holiday and got the maximum overdraft I could, so my bank balance on day 1 of term was always around £0, by the end of term was -£max-overdraft, and then working over the holiday brought me back up to £0... and so on. In my second year I worked part time for the university so that gave me a little extra spending money.
Where is it that she's hoping to go? Costs do vary a lot across the country, I was lucky that where I went (Birmingham) wasn't too unreasonable. I'm now doing post-grad in Oxford, which is a fair bit more expensive BUT the university's much better at supporting its students when they're in need (same with Cambridge IME). Most university's now have quite good resources online to estimate costs, do have a look at the relevant ones for your DD.
I hope that's vaguely reassuring - I think it's wonderful that you're researching it for your DD and would strongly recommend having a quiet word with your DH - he may think he's being helpful encouraging her to be 'realistic' about costs but encouraging her to stay near home is a massive mistake imo. She should go to the place that she wants to and is best for her course, and she can afford to do that without your support if she has to. She might have to make a few sacrifices (shopping at Aldi, walking rather than bus, library instead of buying books etc) but it'll be worth it to go where she wants and where the course is best. And if you can afford to throw a few quid her way every now and again, that's a bonus!