It all depends on your clients and which platform they choose to use in order to post reviews and research the companies they are looking to use. Yelp may be one of the most used. It is important to have a link to your web site on all of those platforms you can find and add loads of photos there with details for each image. Having an effective web site that will sell them on your service or products is imperative. Although, most small business web sites are rather lame: lack of info, price examples, good clear photos which can be viewed full screen for a better look, and testimonials that are not too good to believe.