Hello,
I am well experienced in webmin and virtualmin and i have done similar projects here, which you can view on my profile.
Let me know your webmin and server root ssh so i can trouble shoot the issue.
If the issue is simple and straight forward , i will take one hour charge of 20 or else we will go with hourly rate of 15Euro per hour.
If you have any query, feel free to ask.
Thanks.