Review In Demand Plumbing

First off, great site!  Its clean and simple.  The offer is upfront.  Very organized and to the point. I could go on but you get the point.  With that said, in my experience, declining rankings doesn't necessarily mean something is wrong with your site.  I've personally seen my site rankings change based on traffic.  For example, if I run a facebook promotion, my rankings will jump.  But if there is a gap of about 2 months, then they'll fall.  In looking at your site, I don't see anything that could be a detractor.  I'd probably pay more attention to your site traffic statistics using a site like Google analytics to determine if there are any concerns with my page.  Additionally, Google analytics offers a feature called in-page analytics that shows you where people are clicking in your site and what links or pages they're ultimately bouncing out of your site on.