call your local auto shop and ask. i would say less than 500. you may need to buy new spring insulators and strut bellows. if you are mechanically inclined you can rent the spring compressors for free at an auto store.
turnttoast, After you've installed them I hope you will post photos of your lowered RAV. Also, if you feel inclined, I'd like to know how the springs affect ride and handling. Thanks in advance.