I don't know if this helps but this is what i got as errors using chrome console, some resources are not loaded and there is undefined object passed to the popeye i believe
Resource interpreted as Script but transferred with MIME type text/html: "http://bestinvest.ge/js/script.js". header.js:2
(anonymous function) header.js:2
GET http://bestinvest.ge/en/upload/sresize.php?src=building/uploads/41/&w=160&h=110 400 (Bad Request) /en/?transaction=3&minrooms=1&maxrooms=100&minprice=&maxprice=:739
GET http://bestinvest.ge/en/upload/sresize.php?src=building/uploads/41/&w=280&h=180 400 (Bad Request) /en/?transaction=3&minrooms=1&maxrooms=100&minprice=&maxprice=:746
3
Uncaught TypeError: Cannot call method 'show' of undefined jquery.js:8480
jQuery.fn.extend.fadeTo jquery.js:8480
showImage jquery.popeye-2.1.js:288
$.fn.popeye.each.$self.mouseenter.ismouseover jquery.popeye-2.1.js:642
jQuery.event.dispatch jquery.js:3332
jQuery.event.add.elemData.handle.eventHandle jquery.js:2941
Hope this help, good luck