Wax melts using beeswax

[ProudGrandma]

I want to learn how to make those scented wax melts using all natural ingredients.  The part I can't seem to figure out is how to scent them strong enough to give scentsy or other companies a run for their money.  

Might someone here have an insight into this?

I thought about essential oils, which would probably work if I use enough... but that isn't really cost effective. 

Thanks for your thoughts.