What happens if you don't set up gas/electricity before moving into your new house?

Read your lease. It probably requires you to set up utilities upon move-in.

Your lease also probably requires you to maintain the property and to immediately report any maintenance issues. So if the pipes burst because you didn't heat it or the house molds because you didn't ventilate it or it's eaten by carpenter ants because you weren't there for a few months, you are now responsible for the very expensive damages.

So yeah. Read your lease as this is probably a non-issue.

When you take possession of someone else's property you aren't entitled to neglect it without consequence. Houses need to be taken care of by their residents.

That may not be an option. Many leases state you must keep the power on for the duration of the lease. No the service providers will not allow you to build up a debt. If you fail to set up services before move in then you will have no services.

If you don't set up the services, then the lights and the furnace won't work, obviously.

You can't "build up a debt" - the services are physically turned off.

The lease with my tenants stipulates that the utilities must be transferred into the tenants' name before they will receive the keys to the property.

Check your lease to see if it is the same. Otherwise, if you do not have the utilities turned on in your name, you will not have power or gas.

The utilities may remain on in landlord's name or not be turned on at all.

It will not be available to you until you open an account with the utility company.

you won't have gas or elec until you set it u

Well then, you walk into darkness and go looking for your flashlight.

It wont be on when you move in.