30 Down-and-Dirty Tricks for Big DIY Savings

Get a free smoke alarm and/or carbon monoxide detector. As part of a national fire and poison prevention initiative, many state fire marshals and local fire departments offer the life-saving devices at no charge to low-income homeowners and renters, as well as seniors.

Cost: $0

Savings: About $40 for a smoke alarm and a CO detector.

Bonus: Many departments handle the installation, too.