You won't regret getting a good socket and piece of pipe. I've pieced together various extensions that help me get at the front and rear wheels.
I have found it is easier to break the rears loose with help, because it is such a deep reach inside the wheel. Alternately, support the extension with lumber or whatever else you use for leveling.
Also, things like WD-40 and PB Blaster will work magic if given enough time. But it can sometimes take a few weeks of repeated soaking so that may not meet your time requirements.