£300 isn't much though - a service on the car and you'll be done for the month. That means no disposable income at all - not even a pint after work on Friday.
This might be unpopular, but you are spending £3200 a year on a car (insurance/loan). Get rid, buy something cheap to get you around for a while, if work is 5/10 miles away you aren't doing loads of miles.
I think you need to look at "house stuff" you might also need initially - linen, kitchen utensils/cookware, crockery/cutlery, maybe the odd bit of furniture etc.
On the upside I think you might be over estimating utility bills - I can't remember exactly but I think mine are something like £80 a month.
ETA: The house is unfurnished, so you'll need everything - bed, bedside cabinets, sofas, coffee table at a minimum.