Hi dear, i have POS system ready to deploy, i have developed it on C# and mysql. It can be used offline and online with android reporting. I will send you screenshots right when you will chat because i cannot attach it here with the bid. it is with barcode system as Well C# and my sql is the most stable platform for POS.
I can also work on Different Open source POS systems e.g. NEXT ,Open bravo etc
i can modify it according to your requirements within a day or two. So please contact me so that you can start your work ASAP