If you are modelling in Fusion you can use it to calculate masses and loads. This is a really good way to back up your spreadsheet weight calcs. Here's my "hack" at ours:
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We are running 24v starter and 12v box voltage. We have installed a Victron based system and use an Orion Buck-Boost to manage charging between the two.
I just installed an airhead - not used it yet. It was easier to get in the UK, I'm not sure there's much between the airhead and natures head.
We used Outbound windows. I am very happy with them, but being glass they are heavier than the seitz type.