Backcountry and Amazon have the Weehoo iGo Two Bike Trailer for $365 with Free 2-day Shipping. I chose to order through Backcountry because of the 4% cashback available. These retail for about $520 and have been as low as $400 according to CCC. The two seat version is longer than the single version. If you are only riding with one child, you can remove the second seat and put a basket in it’s place or leave it empty.
Backcountry Link
Amazon Link
Enjoy!