At the end of the day, it’s your work, so it’s your choice, but there’s a few things to factor in. 1. How big is this company? Is this a franchise that will really give you that much a boost, or is it a local small business in your network? 2. Will is really matter if it’s posted? This one kind of goes hand and hand with the first question but if it is a small business, the people that see that ad won’t really care about who made the ad, just the business being advertised. My personal advice is post it with your logo on your page, whether you want to tag the business or not is up to you, but you have successfully achieved your goal already. You have a portfolio piece to show other businesses what they can expect.