As best I can tell the Zync comes in three versions ($200, $500 and NPSL). I realize the Zync NPSL has a internal spending limit based on credit history, score and spending patterns - but what is the minimum initial spending limit?
That will be based upon a variety of factors such as: credit score, utilization, income and assets, other lines of credit you have, credit history, history with amex specifically, etc. Best bet is to call customer service and ask them what you current starting limit is. Mine started around 2,000 internal limit and quickly grew to be much much higher. I currently don't know what mine is at but have never had problems.
As any NPSL charge card, they need to view your spending pattern. When got approved for mine, I check the 'check my spending' and it was approved for $3000. SO i presume it might have been a little higher. YMMV
I tried it twice for giggles: $2000 approved, $5000 not approved.
$2000 is around my high balance on my other tradelines (though recently racked up 3.5K fixing wardrobe / insurance payment / other one-time events) and $5000 is the CL of my highest tradeline.
Attempting to back-into the Amex NPSL math, at my listed income I have around 6700/mo post-tax; average housing payment around here is probably 2.5Kish, my car payment(s) (refinanced recently but the old Wells loan is still reporting) would be 850ish technically, and utilities / cell phone / etc are probably another couple hundred, and food probably 500ish in their metric. So $2500-3K would probably be about mine too if I tried it again I suspect.