The best place to start if you need help with a specific product is to contact the developer. All WHMCS Marketplace developers have both a website and support URL listed.
First Release
Resell VPS & Cloud Dedicated Products from Liquid Web
Automate the sale of VPS servers & give your clients the ability to completely manage their VPS server inside of WHMCS, using the industry leading SolusVM control panel.
Harrison Venter @harrison8038
Terrible Module...
Stay away from this module...
After adding a server it will start showing out of stock within a few days and you will constantly have to add new servers its just a headache.
Also I tried contacting support not only did they somehow lose my account they also have still not provided a solution to the issue 2 weeks later.
ARP Host @barry2916
This is awesome I can now resell Hivelocity Dedicated Servers the best Dedicated Server company!