If you don't have a friend who can lend you the books, online message boards are excellent places to find used (sometimes free) LEED Reference Guides.

While free LEED reference guides are hard to come by, free information is available at the U.S. Green Building Council Website. The USGBC offers a lot of free material including a partial reference guide. Also, the Green Building Certification Institute offers free information on the exam as well as free LEED AP sample exam questions and helpful tips for passing the exam. It is important to use a reputable source for the information you are using for the exam because the materials are updated constantly.

There are also many LEED Reference Guides available today to help individuals study for the LEED AP Exam. A few of the LEED Exam Prep tools, such as those sold by Green Exam Prep and PPI, have been vetted by thousands of people and come highly recommended by those who have used them to study for and successfully pass the LEED Exam to become LEED Accredited Professionals. These tools are not free, but in terms of the overall value they may provide in helping you become a LEED AP, they may be worth the money.

There are also used guides available on Amazon.com, eBay and through the ARE Forum, but you will have to pay for them.

Good luck!!
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