hi,
We specialize in VPN and related websites. To give an outline, to setup a VPN server you will need a dedicated webserver like a VPS and then the istallation itself willl cost you about 700 USD and then its related website, admin panel, customer panel and other things will cost you about 300 to 500 usd . This is just a beginning. After that it will take about 2 to 3 months to stabilize and monitor the server and hand over
This a trusted method and will work for you. We need to install CentOS, mysql, php and Radius for the VPN.
If someone is going to charge you less than this, then please double check if they will give you everything to start a VPN server. We are available to answer any questions you may have,
best regards,
Arun