When hiking solo, you don't have the option of leaving one car at the destination trailhead. The easiest solution is to choose a loop hike or at least a loop that leaves you minimizing the trail distance you have to retrace. Look for "near loops" where you might be able to add a short road walk to complete the loop. Even better, use a bicycle for the road portion of the trip. I've often used a bicycle to complete a loop. I have ridden on paved and unpaved roads....