Off the Grid Listening-HELP!

In the next year, I am going to have to move my dedicated listening room to being off-the-grid. I would love to hear from anybody with experience in this area.I am just in the beginnings of doing research, but if anyone can accelerate this process I would appreciate it. I would need to power my turntable, a phono pre, tube pre amp, tube mono blocks and a couple of class D sub amps. I know that I need a pure sine wave inverter (how big, what brand?) and a couple of deep cycle batteries. Is there any easy way to calculate the size of the inverter and batteries needed? 12 or 24 volt system? Would something like a PS Audio regenerator be helpful too? This would only best used about 8 hours per week in four hour sessions. Thank you!