I did a basement remodel where the floor drain for the toilet was below the grade of the sewer connection. The difference in elevation was that the sewer connection was right at the floor level, which was too high for a regular toilet. HOWEVER, we found we could install a wall mounted toilet (you see these bolted to the walls in public buildings a lot) where the drain pipe was actually in the wall, rather than the floor. That gave us the necessary rise in elevation for the drain, so it worked really well, without any pumps, augers, etc.
Good luck James, and the property issue sounds like a complaint to the county more than anything else.