I bought an inexpensive tow core areator this spring and used it on 1.5 acs with good success. It is an Agri-fab, I think the same one TSC sells; however, I got mine at Lowes ($219). It took me about 1 hr for assembly, and the quailty was better than I expected. I have a lot of clay in the soil and it was extremely compacted. Around the house, I watered the lawn to help loosen the soil for better penetration. The unit says you can put 170 lbs of weight in the tray, which you definitely need. I did areas away from the house after a rain.
Be sure to get a "core" areator instead of the spike kind, in that the spike kind does not help soil compaction like the core aerator.
This unit does not have anything that can greased, but for the price it's a decent aerator. My next step up will be something like a Woods 3 point.
I have noticed a BIG difference in the health of my lawn after areating.