$250-month in insurance divided by $3.00-gallon of gas = 83.33 gallons a month. Time 18 miles to the gallon = 1500 miles a month.
If you drive your honda less than 1500 miles a month, you can do better by just driving the Toyota, than driving and insuring both. This comparison totally disregards possible repairs, maintenance, license and regestration, but it should help. If your gas costs and gas mileage are different, just plug them in to see what your numbers are.
