At 1 point during a frigid winter, our gas bill was almost $1000 ! 

Electricity/gas.

But, you will (probably) want to have them call you about any water leaks.  

This can be tricky from a warranty perspective as if one is the plumber and you have a massive leak it will be very difficult to determine which sub caused the damageNot to see it can't be done, but it should be at a considerable discount

My dad and I want to purchase a gas station and I don't really work as a real estate agent.

We have the 2nd highest Gas Tax in the lower 48.The Governer is trying to put into law, a tax on the amount of miles that you drive each year.A recent poll found that at least 50% of the Residents would leave this State if they could find a way.Raymond

Here, it costs a lot more to heat with electricity than to heat with gas forced air.

As a contractor I always prefer a full gut but it does eat away the rehab cost and takes longer but no stress about plumbing, leaks, electric, lead paint and etc in the future.The patch up would cost less, fast timing, but then you are gambling with what's behind the wall and hoping nothing happens in the future.I assume most house that are purchase for BRRRR purpose are in distress/bad condition and old on some occasion.What rehab number would you go for?

Also a couple of the burners won't light without holding a lighter to the gas.

Found a small leak in the celling.