Cheaper to have heating on all the while or fan heater?

[nctf]

So we rent a bungalow, it's freezing in this house! Is it cheaper to have the gas heating on low each day or to have a little fan heater on? I also have a heated blanket, but I have a 3 year old and 7 month old so isn't ideal for them.

What else can I do to keep the bungalow warmer?

I would use an oil filled heater rather than a fan heater if it's only 1 room you need to heat. If it's more than one room you might be as well using your gas central heating

Thanks @dementedpixie will have a look at a oil filled radiator.