Ford Crown Victoria/Mercury Grand Marquis GS/LS primer:
I am going to go and say, Get a nice condition 1988-1991 Crown Victoria.
The 1988 one I had, was anvil reliable, cost virtually NOTHING to run, just gasoline, oil changes, and every once in a while, brakes and a battery.
For being the cheapest car to RUN, dollar for mile, that I ever owned in my life, nothing can beat them. These are the ones built from 1979, so the body style and durability of the RWD, BOF, cast iron block, traditional American sedan that to THIS day are still bought by the Police and Taxi companies which beat on them and get 300,000 to 400,000 miles on thesm
You can put furniture, bicycles, all kinds of stuff in the trunk, actually carry 5 people in them, not worry about theft, and gas mileage on regular will easily hit the high 20's on the freeway. and you get some fair amount of comfort and safety.
These are so good that if looked after, they will run to 300,000 - 400,000
If you look around, you can get a nice one with low miles for about $1200, and $2500 puts you in to "mint condition" territory.
Specifically, look for areas of rust, collision damage that was fixed, cracks on the dash (espeecially at the front speakers) and the 1/2 vinyl roof, weak or non working locks and windows.
Most everything else is bulletproof, the EFI motor, the $2500 AOD transmission, (dont buy one with a bad transmission), Air conditioning, and thd body is sturdy. The LX versions abound, (LS in Grand Marquis) which give you leather seats, turbine look steel wheels, cornering front lamps and other things.
They don't have great handling, the rear brakes are drum,
the '90 and '91 have driver airbags (with teeny twin horn buttons) and they are quite safe and comfortable.
Just go to a junkyard, buy a steel wheel with a used tire on it, and discard the donut spare, and you are good to go - for YEARS!!
What is not to like?
Side note: If you want a newer car than these take a look at some of the old Crown Vic Police Interceptors on ebay. They usually have about 100,000 -150,000 and have Heavy Duty frames, batteries, radiators, AT coolers and oil coolers, full size spares. DO avoid the "vomit comets" (patrol units that carried prisoners) and "Dog Units" (K9 ones really smell) but $3,000 can get you a good one if you shop around, and the best are Detective, Captain's, water Dept and DEQ ones that are unmarked, in regular colors, but they are few and cost more, most P71 interceptors were white.
You can browse ebay
http://motors.listings.ebay.com/_W0QQa39Z1946QQa41Z10496QQalistZa39Q2ca41QQdfspZ2QQfromZR42QQfsooZ1QQfsopZ9QQgcsZ13QQpfidZ2473QQsaca tZQ2d100QQsbrsrtZdQQsocmdZListingItemList
100,000 miles is NOTHING on them, and sometimes you can find one with low miles that has been lightly driven by a senior citizen (who bought their cousins: namely the Grand Marquis Mercury.
They were good sellers, (110,000 Crown Vics back in 1988) so plenty survived, so you can relax and lookd for a real nice one.
Dollar for dollar, an absoultely worry-free, unbeatable value for what you get back.
Your friends will laugh at you for driving a grandpa car, but you will have the last laugh.