Just write the deposit off and if you get any back, consider it a blessing. It's odd that you give it so much weight when it's usually less than a single month's rent.
I recently moved, and the landlord (who was broke) was trying to keep money for all sorts of non-existent faults, most of which were due to his shoddy DIY work before I moved in. I raised a dispute and eventually got the vast majority of the money back. Just make sure you keep pictures of the state of the house before you move your stuff in.