Hi,
I have read your requirement carefully.
I am very familiar with NFC.
I use various NFC tags, NXP, Mifare classic, NTag(213,215,216...), ICode, etc.
I am developing NFC drivers, to read/write data, protect with passwords, format NDEF, Factory, etc.
I have rich experience to build POS app, membership card app, security app based on NFC.
I have done project similar with your project.
Please have a look on my previous works.
https://www.freelancer.com/projects/html/DEMO-Android-App-for-Incident/ https://www.freelancer.com/projects/mobile-phone/Android-NFC-NTAG-programming-tool/
Let's discuss more detail via private chat.
Hope to kindly reply,
Peng