Need an experience javascript person

Hi All, I need an experience javascript or jquery person who have experienced in timer scripting. This is a very basic work but I want a person who also know how to stop/reset server timer where a website host. Basically I am working on a ads click earning website where timer is running but when I am stop timer of 1st ads and then run another ads then it show error and ask to wait for 60 or 50 second or something like that. I will share website link in PMB with a deserve and expert developer only. Please don't bid if you don't have previous experience about that. Budget $20 maximum. Thanks