It might be just me... but for a big project like this that will ultimately create considerable mess and dust, I would first start by cleaning everything up. Counterintuitive maybe, but I want to see what the project really looks like, without dirt, mold, and whatever else might be in the way of a clear look-see.
Like, buckets of wash and rinse water, soap and bleach (we use "Soft scrub" for problems like this)m and a bunch of clean rags. Clean and rinse and repeat, and repeat. Finally, like a woodsman that cuts away the underbrush and small trees first and then can really get at the trunk of the tree to be felled, you can really get at the main chore(s).
I often find that things are a lot less intimidating once all the old dirt and stains are gone; it's then easier to really see what to do to reclaim the surface. It also lessens the chance of later sanding and stirring up 'whatever', causing respiratory problems for the both of you.
Advice given freely, by strangers, over the internet, and valued at that price, too!
Like, buckets of wash and rinse water, soap and bleach (we use "Soft scrub" for problems like this)m and a bunch of clean rags. Clean and rinse and repeat, and repeat. Finally, like a woodsman that cuts away the underbrush and small trees first and then can really get at the trunk of the tree to be felled, you can really get at the main chore(s).
I often find that things are a lot less intimidating once all the old dirt and stains are gone; it's then easier to really see what to do to reclaim the surface. It also lessens the chance of later sanding and stirring up 'whatever', causing respiratory problems for the both of you.
Advice given freely, by strangers, over the internet, and valued at that price, too!