Hello sir,
my self hardik and i am python developer.
I am currently working into the ERPNext and based on that I can solve your issue.
In Erpnext I have did following task with for both in cloud Erpnext (online user) and local user(localy installed)
1) Customized existing doctype.
2) Customized existing report.
3) Develop new module or app.
4) Integrate payment gateway (Razorepay).
hope we will get back to soon for further discussion on your requirements.
Thanks for your time.