Hi there moonpig and welcome to the forums!!!
First things first make sure you cheack out this thread as it can be very important and helpful!!!
Its pretty cool that you gave us a short back group but were gonna need to know a bit more about you to help you out the best way we can 
.
check this thread out to see how to qualify for a gc
https://pheromonetalk.com/t/how-do-i-qualify-for-a-25-gift-certificate/19934
Regarding you and your friend wanting to experiment what types of experiments are you guys looking to do? Also what age are you as this can help us further evaluate what type of mones to recommend.
Anyways hope you respond back soon =D