Every time setColor gets hit, you are setting count = 1. You would need to define count outside of the scope of the function. Example:
var count=1;
function setColor(btn, color){
var property = document.getElementById(btn);
if (count == 0){
property.style.backgroundColor = "#FFFFFF"
count=1;
}
else{
property.style.backgroundColor = "#7FFF00"
count=0;
}
}