I'm looking at putting a 4th car parking spot along side my garage. This will mainly be for parking my enclosed trailer. Has anyone done a similar project? If so, would you do anything differently the next time around? What size blocks should I use - 12" wide or the bigger 16" ones? Tonight I am going to get the a measurement of how high it will need to be but I am guessing it will be right around 2' (give or take 3" to 4"). How much base should I put down under the base layer block? Also, do I need to run drainage on a small retaining wall like this? I plan on having crushed concrete or something to that effect for the top layer this year and then maybe pave it next year. Any thoughts on that? Here are the pictures of where it will be located. It will be about 13' wide on the back of the stall, 23' alongside the garage, and 20-23' of wall coming from the driveway. Total - 56-59' of block per layer.