Short answer: much more than you budget for!
Longer answer: you should sit down and discuss your daughter's finance with her at every opportunity to ensure she does not get into more debt than is necessary. Whenever she come shome, for holidays or weekends, check what her financial position is. Saving up isn't the answer - your daughter getting a job that suits her while she studies and provides valuable work experience / summer work is the best way forward. Earning money will make her value it more, and she will be ahead of others when she graduates if she thinks about her employability skills whie she studies. Find out if there is the option to do a placement year on her course - a year working in industry where she can develop her practical skills (often resulting in a better degree result!) and work towards reducing her debt.