What I'll do is narrow an audience so that I can cover the entire audience with $1 ads with my budget.
I narrow an audience down to a population of 90,000
My ad will give me a potential reach of up to 1,200 for $1
So I run 90,000/1,200 = 75x$1 ads
Surprisingly many of them will convert for me, at which point I cut off the losers and let the $1 ads run until they show consistency and then I start upping the $1 budget.
I've been using this strategy with pretty good success.
Does anyone else take a similar approach with their Facebook Ads?