Pinch your pennies. Ebook self-publishing has become something of a gold rush. Everyone is rushing to do it, but the people who stand to make the most money are the ones selling the pots and pans. The cold hard truth is that most ebooks -- whether traditionally published or self-published -- don't sell well. You, as the self-published author, are the publisher. You're running a business. If you run your business profitably, you'll survive to write another day. If you're losing money, you'll eventually be forced out of business unless you're financially secure through other means. As a small publisher, you can't easily control your sales, but you can control your expenses. Minimize your expenses.
Long article, but great advice from the founder of Smashwords.