Advice on quotation of a 15' documentary editing

Hi folks. I'll probably need to quote a 10-15' editing of a documentary.
It will be delivered in 4k. The footage will come from Sony 7sII, BlackMagic Ursa Mini Prores and some DJI Phantom 4 pro footage. The documentary features a rock climber trying a very difficult route. The story would be about this route, his obsession, the training, the attempts, etc.
While the project has some sponsors, it is not a TV production, and there is no big production companies behind. It just the cameraman, directing the documentary, and me, doing the editing in fcpx. I'll also probably do the colour. We'll try to get the music done by some independant artist.
We guess that the editing will take us one month and a half.
We'll need to find a way to work via internet (frame.io?) because the director is in Europe and I'm from South America.
Any help on how to quote this will be appreciated.

How much do you need to cover overhead costs, and make a living for a month and a half?