Forget about the invertor and trying to run a microwave or any other power hungry device. I use about 75AH/day for a 12v CPAP, charging camera and computer batteries, etc. I have 270 watts of solar and two large AGM batteries for a total of 300 AH. I wish I had more!! Solar is great when the sun is shining, when it is close to midyear and overhead sun and when not camped in the shade. Plenty of times those conditions are not available. Also, do you really want to park in the sun on a hot day just to feed your panels? Plan on having way more capacity than you use and avoid any heavy consumption. If you need your microwave, start a generator. Also remember that convertors and invertors waste a lot of power.