With gas prices nearing the $4 mark, more real estate pros--who get plenty of use of their cars for business--are likely going to eye the gas mileage on cars more closely before making their next car purchase.

The USA Today recently evaluated cars to come up with a list of the most fuel-efficient cars on the market today, based on EPA combined mileage ratings. Industry researcher TrueCar.com also provided the estimates below of the cost to drive these cars 15,000 miles a year at $3.52 a gallon (the national average for gas).

Here are the top five and their costs to buy and drive.

1. 2011 Toyota Prius
   Base model sticker price: $23,810
   Combined EPA rating: 49.6 mpg
   Cost per 15,000-mile year at $3.52/gal.: $1,064


2. 2011 Lexus CT 200h
   Base model sticker price: $29,995
   Combined EPA rating: 41.6 mpg
   Cost per 15,000-mile year at $3.52/gal.: $1,269
   


3. 2011 Honda Insight
   Base model sticker price: $18,950
   Combined EPA rating: 41.3 mpg
   Cost per 15,000-mile year at $3.52/gal.: $1,279
   


4. 2011 Honda Civic Hybrid
   Base model sticker price: $24,700
   Combined EPA rating: 41.3 mpg
   Cost per 15,000-mile year at $3.52/gal.: $1,2792
   


5. 2011 Lincoln MKZ Hybrid
   Base model sticker price: $35,455
   Combined EPA rating: 38.6 mpg
   Cost per 15,000-mile year at $3.52/gal.: $1,368
   

Source: Top 10 List of Most Fuel-Efficient Cars: What’s the Best Buy? USA Today