I am thinking of installing a versa-lock retaining wall in the front of my home. The area in question will run parallel with my new concrete driveway and has a slight slope to it. I am thinking of a wall roughly 17'5"long and about 2 1/2' high(highest point). The wall will gradually become smaller as you go up the drive making it roughly 1-2' at it's lowest point. If I haven't confused you guys yet the main question(s) that I have is: 1. How much versa-lock blocks will I need? 2. Should I use a sand or gravel base? 3. Any other point/tips I may have missed/addressed?