tankless water heater grass valley

Q: Our family of four lives in a four-bedroom three bath house in Grass Valley, California. Our water source is from a private well. Me and my teenage son and daughter seem to use a lot of hot water. Our current electric tank type water heater is leaking and needs to be replaced. Which type of water heater would be best for us: gas or electric, tank or tankless? The current thinking is that gas tankless water heater would be cheaper to operate. What about the possible increase in gas prices in the next 10 to 20 years? We use LP gas.