Money is tight during your time at university, even if you've got family and a loan to support you. Every penny counts, so don't waste hundreds on brand new books from the university bookshop. Lecturers will tell you that you all need the same edition of the book to be able to find the right page, but you can find a second hand version.
Check to see if there are any used versions for sale on Amazon as these are normally much cheaper. Look on eBay, Depop, Vinted, Shpock, Facebook Marketplace, World of Books, and other online marketplaces, too. Or there might be a group on Facebook dedicated to your university or your degree. Here, you can find out if anyone from the year above is selling their old books. Alternatively, see if you can borrow your books from your university's library. The only downside to this is that you can't write notes in the margins, and you might have to take these books out again when exam period comes.