Hello there! If you only want one, I’d go with AMMO although Instant Openness and Ammo would go nicely together, the former isn’t cheap though unless you get a togo bottle.
I’d suggest you go read…
An Introduction to Mones; Names, Size, Strength, Use, Effects & Length of
and
The Snook’s big book o’ pheros for rookies
Also, Phero Color Chart by MuskCloud has a good chart in it that gives you a rough idea of the common use of most of the pheromones sold by Androtics, you could use it to get some ideas for searching for threads/journals.