3- NAC by Metabolic Maintenance (the only NAC product with absolutely no fillers)
To lower costs, NAC can be purchased as a powder which has nothing added such as fillers or lubricants etc. All the things that are usually added to keep the encapsulation machinery working more efficiently.
Powder means you can adjust the dosage more effectively and encapsulate yourself if necessary or mix into water. Getting an accurate pair of scales which can measure in mg is helpful.
Buying bulk works out much cheaper. I purchase 1Kg quantities which lasts for ages.
Thanks for your post, I will keep a copy of it for ideas because it might be helpful to me.