What to do with outdoor hot tub in a northern winter?

[malik]

What to do with outdoor hot tub in a northern winter?
I am looking to purchase a house with an outdoor unprotected hot tub in an area with severe winters. Do I change the water? Is it expensive to keep it heated?
What are pitfalls?

This house also has only one bathroom which contains a whirlpool bath and I like bath oil. Do I just make sure the jets are off when using bath oil? Or are my bath oil and bubble baths over?
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hot tubs