My Book Buying Ban

I have decided to go on a book buying diet. I am taking part in Benjaminoftomes's Project TBR and I really want to get my TBR Shelf down to around 50 books. I have 110 unread books and that doesn't include the books of my Kindle which I have about 10.
I know I won't be able to just stop buying books altogether so I've gave myself some rules:

1. I'm allowed to buy new releases.
2. I'm allowed to buy the next book in a series but I have to have read the others in the series first.
3. Every 4 books I read or unhaul I can buy a new one.
4. I can pre-order up to 3 books a month.  

I'm hoping I can stick to this, I hate seeing all my unread books just sitting there lonely. 

My TBR Shelf