Hi. I can work on this immediately for you toward completion. I've also used WHMCS and related stuff on my own reseller hosting. Total of 10+ years in the IT Industry including two Microsoft Professional Certificates and have been working with websites and hosting for the past few years.
Also, please take a quick look at my profile/feedback and you'll notice I'm a 100% trusted freelancer, a reputation built from perfect accuracy, attention to detail, excellent efficiency and great communication. I strongly believe I'm the perfect candidate for your job and you can be confident knowing you've hired a professional who delivers on-time.
Thank you for reading my proposal and I look forward to hearing back from you toward the start of a healthy working relationship. I'm from the Caribbean so there's no language barrier between us and our time zones should be close as well. Kind Regards, Kenny
P.S. I will also place a bid on your Softaculous project. Perhaps we can discuss a combined price for both projects and I take care of everything for you.