Facebook Contest

After a few meetings, my business partner and I decided to host a contest for Midwest Automotive & Diesel as well. It will take a little while to get the contest details in order with the "fine" print. Both of the contests will be hosted on our Facebook pages (Pro Computer Solutions, Midwest Automotive & Diesel) It will happen pretty soon. I was thinking for both businesses it will be a prize drawn from the fans of the page if the fan count reaches a certain number in a set amount of time. For Pro Computer Solutions the prize will be a free PCS 100 or comparable computer. For Midwest Automotive & Diesel the prize is yet to be determined. We were thinking either a free service, such as an oil change/tire rotation, or maybe just a gift certificate. I am really looking for feedback on this, as this is the first time that I have tried to do this type of marketing.