Qualified Firefox automation

I am looking for a freelancer to help me with Browser automation. I am using Waterfox (a firefox clone) on Windows Server 2012. I have a few dozen (and getting more every day) of Waterfox profiles, each with unique cookies and custom settings (user agent, about:config changes, proxy server). I need to open them daily and perform a few simple tasks on a website (filling out a form and clicking buttons). I would need an automation that does this for me. My goal is to have an list (excel, csv,...) where I can write down which profile the bot has to open and which values it has to fill out on the website. Then check if submitting was ok and return OK/not ok on the list. The automation has to be reliable, because it shall run unattended. I am thinking about Selenium, though it can be any professional solution. Requirements are not 100% clear yet, and also will change from time to time (eg which buttons to press on the website, include other websites too), so I would like to hire somebody per hour. The project is not big, actually only open the correct profile and fill out the form. In the future only small adaptions (different forms, different buttons) will be necessary. Thank you for your interest