Even though I don't drive very far, I did something similar.
I figured that it was getting very expensive to keep refueling my 11-mpg Cadillacs, so I went shopping for something more fuel efficient so I could still keep my Caddys and drive them about once a week.
I didn't want something small- I wanted a large car that got good fuel mileage and kind of recent. I decided on a 1990s car, either Cadillac or Lincoln. I heard many more good things about '90s Lincoln's compared to Cadillac's so, I decided on the Town Car. They have a better-than-average repair record.
I narrowed it down to '94 or '95, then decided on '95 because I like the controls on the steering wheel (cruise control, radio volume and tuning and a/c fan speed) and because the '95s had a 2.84:1 1st gear ratio compared to the 2.40:1 on the '94s.
After a 3-month search, I found a very good '95 TC Signature, 109,000 miles, original owner with all the service records, grey, leather interior, etc.
I am very pleased with the mileage I am getting from this 4,200 lb, V-8, large car. The range has been 17.8-24.3 mpg, with the current average at 20.6 mpg. Some TC owners have gotten as much as 28 mpg on all-highway trips.
Acceleration is pretty good, too. Car & Driver tested a '95 and got a 9.0 sec 0-60 mph time and a 16.9@83 mph 1/4 mile. A lot of luxury and 20+ mpg!
As planned, my two Cads ('69 Fleetwood Brougham and '76 Fleetwood limo) are driven once every 7-10 days. A tank of gas lasted in my '69 from Nov. 3 to Jan. 10.