Google Maps freezes on listing page

Hi, I have a problem with google maps freezing. When I click on an ad on the home page it takes me to the ad details and image page. There is a google map that displays with the listers location. When I mouse over the map I can scoll in or out for a second or two then it freezes and wont respond by scrolling or clicking on the + or -. I am currently working on the site through localhost on my computer and connected to the internet. Could it be due to the site not being live on a hosting site? Can anyone help?….cheers