How many lifts are you looking at leasing? If 1 is the answer, I'd lean more towards propane. I have many customers with 1 lift truck, and ones that have electric never are able to charge the battery as they should. The downside of not chargine the battery correctly is shorter battery life.

The battery should be brought down to 20% charge (or 80% discharge) & then be allowed to charge. Most single forklift operations find this extremely difficult to do. No one wants a dead forklift when they need it, so overcharging is the name of the game. The result- a battery which should last 8-10 years ( in your enviroment) lasts about 5 years max. Batteries are expensive ( around 5 grand) so no one likes to hear that it didn't last as long as it should have.