Both the ones you circled are Murphy's patternless geckos that start out with a faint irregular beige pattern that disappears. The one in the green circle may possibly be an albino Murphy's patternless, but I can't really tell. It's not a regular albino despite its coloring. The white tail and fading irregular beige pattern give it away. As far as why there is color difference, the patternless can sometimes vary in color a bit with mood and temperature.