Hi Instinct, welcome to the forum!
Each to-go bottle holds approximately 40 sprays. And the amount of Ammo you would need might be one spray or maybe two. That amount is something you need to determine, this post should help How To Find Your Sweet Spot (How to find your sweet spot...)
In order to make the best recommendations for you, and also get you qualified for the $25 gift certificate, please share some info about your personality and how you relate to others. Are you shy? Are you outgoing?
Also, what kinds of things are you thinking of using pheros for? Work? School? Romance? What kinds of effects do you hope to see?