The Money Advice Service offer a great budgeting calculator which is free to use and lets you see in plain terms how much money you need for various things when you get your new home.
Make sure you are prepared to work on the calculator. Get some bank statements together, any utility bills you might have and any payslips you have to give yourself an idea of your income.
If you’re still a bit unsure of how much money will be coming in, you can start by entering rough figures to give yourself an estimate of how much you think will be needed in each of the categories on the calculator.
The benefit of using the Money Advice Service’s website is that you can save your figures. You can retrieve your figures and go back and work on them or amend them and start again.