Sounds like you might be a good candidate for an on demand heater. There are good versions in gas or electric, although the electric will require some rewiring, if you have enough amperage. 200 amp service seems to be what most require.

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On some nights I still believe that a car with the fuel gauge on empty can run about fifty more miles if you have the right music very loud on the radio. - HST

1983 300SD - 305000
1984 Toyota Landcruiser - 190000
1994 GMC Jimmy - 203000

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