Rent a wreck
We have Rent-A-Wreck agencies in RI where you can rent a beater car for about $25 / day. Rent one, put lots of couch cushions between the bumpers or old tires wrapped in blankets or just use people you don't like very much and ease it up the hill.
Also, Home Depot also rents small trucks for $20 for 4 hrs if you buy something.
If you are really desperate, you might try putting a socket & long handle rachet on a lug nut on the passenger side front and back wheels at the same time. By "tightening" the lug nuts, the car will probably roll uphill easily without over tightening the nuts. Maybe loosen one and torque it on while trying to roll the car to make sure you won't be over-torquing it.
Good luck,,
Bob