Or at least have the ability to be easily switched over?

My furnace has failed and needs to be replaced. I currently have oil and there's no gas in front of the house but I know as soon as I replace the furnace they'll extend the gas line. Anyone have any recommendations?

My house we originally equipped with natural gas a/c. I was never happy with it and subsequently have replaced the system with conventional natural gas furnace and A/C. It never cooled to my satisfaction. Truth is it was only 3.5 ton unit; replaced with 5 ton. More than one HVAC salesman told me I was making a mistake. I didn't, we've been much more comfortable and no appreciable increase in energy bills.

Had a similar problem when we moved here...ancient heat pump went tits up and natural gas was still a couple of years down the road. Hated heat pumps so bad we installed a new gas furnace jetted for propane until the natural gas got here. Installer left the natural gas jetting kit inside the furnace and it was a 5 minute changeover when the time came. If you know that the natural gas is coming for sure, you might want to consider a similar arrangement or just blindly convert to propane and keep hoping to get lucky later.

You can get a unit that burns oil & wood. That is what was in my house when I bought it and could not be happier. It's really nice to have when the power goes out in the winter.

One or the other.

Gas fired equipment can be converted between LP/Natural.

So if you think Natural will be an option, you could have an LP tank installed until Nat becomes available.