15 hours per week or about 2 hours per day usage is just fine for a reach truck, i think you will not need a spare battery but you should train your operator on the proper handling of the battery because it is the heart and soul of the electric forklift. Another area to look into is the pavement. Reach trucks has a smaller wheel compared to the rider type therefore uneven pavement would reduce the service life of your reach truck. You did not mention whether it will be use in a racking system, however you have to consider the right stacking angle of your forklift when operating on a racking system, the collapse height and the lifting height at the highest level because there is danger that the backrest will hit the roof if there is any. Lastly please considere buying the TOYOTA brand.