I am looking to purchase the Retevis RT-97 Repeater. I want to setup the Repeater in a shooting house on my father's property, which is the highest point. I plan to mount the antenna on the tin roof, along with a solar panel (to keep the battery charged), which will power the RT-97. The issue I am running into now is not knowing which size rechargeable battery I should use to operate the RT-97 and safely leave it unattended. Any suggestions or red flags to my ideas would be greatly appreciated.