And the 25k price is "shore power," the off grid package is another $2800!
Water to wash with can be the harder part. Though having a dryish cabin, there's some convenient USB chargeable pumps that fit on a 5gal jug and little submersible USB chargeable pumps that get you a poorly pressurized shower nowadays from a big pot (which can be warmed on a woodstove, or sous vide thingy).