Tech support personnel

I have a website that sells different kind of software (about 20 things in total). While most orders are for specific items, there may be orders for any of these scripts. I need tech support personnel who will answer technical questions and do script installations. You need to be familiar with php/MySQL scripts. They are not difficult to install and come with instructions. The website isn't high traffic so this is a part-time job, not full time. The budget is $200/month. You will need to answer technical questions within 12 hours of their receipt, preferably as soon as you an. You will need to do installations within 12 hours, preferably as soon as you can. Availability on the weekends is a plus - or at least some sort of limited availability. You will need to be fluent in English so that you can handle customer emails. Please PM me what experience you have. Thank you.