Thinking of having the exterior of your house painted [1], but you're looking for ways to save money on the project? Whatever you do, don’t buy some cheap-o bargain paint. Cheap paint is never a bargain.
When figuring the true cost of a big paint job [2], measure that cost on an annual basis and include both the cost of the paint and the cost of the labor. The longer the paint lasts, the lower that annual cost becomes. 
Here’s an example, comparing top-notch premium paint and standard paint:
Premium Paint
Labor $7,500
Materials (20 gallons @ $25) $500
Total Cost $8,000
Estimated life of paint job: 10 years
Cost per year: $800
Standard Paint
Labor $7,500
Materials (20 gallons @ $15) $300
Total Cost $7,800
Estimated life of paint job: 5 years
Cost per year: $1,560
So as you can see, even though “bargain” paint may save you a couple hundred dollars at the time of purchase, it won’t last as long as premium paint once it’s on your house. You’ll be needing to repaint a lot sooner than if you’d invested in top-quality paint to begin with. If you always use cheap paint, then over the years, you’ll be spending more on your bottom line to paint your home more often.
Use high quality paint and have your home painted much less often, and save money in the long run.
Links:
[1] http://www.moneypit.com/article/exterior-home-painting-tips
[2] http://www.moneypit.com/javascript%3Avoid%280%29/%2A364%2A