Read https://www.amazon.com/dp/B07Y1BHJMY/
It's a very short book and a fun read. Will help you figure out best pricing for your situation.
It sounds like you're in a good ballpark price wise! Which is very unusual. Most people in your situation undervalue thier time and talent.
Here are some wonderful resources to help you with your journey.
60-70% is generally the target margin. (not markup)
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To answer the question: I charge them US Dollars.
Here is a great book on this exact issue. https://www.amazon.com/Package-Price-Profit-Essential-Packaging-ebook/dp/B07Y1BHJMY Nigel has a great community that I am a part of.
The full title of the book is
Package, Price, Profit: The Essential Guide to Packaging and Pricing Your MSP Plans
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Edit add price : the price I can see is $1.10
Read Nigel's book: https://www.amazon.com/gp/product/B07Y1BHJMY/ref=dbs_a_def_awm_bibl_vppi_i0