here are some older pics of my darkroom.
I got rid of the two enlargers a while ago and now have a devere 504 with varicon head on the back wall.
the sink was bought from a dog grooming parlour that was closing down - it's perfect.
I'll have to take some snaps of it as it currently is.
As for green chemicals ... there isn't really such a thing. There was a company making a range of "greener" chemicals a while ago,but I cant remember what they were called, and I cant find them anywhere now, so I expect they've stopped anyway. The thing is, the concentrations and amounts that you'll be using as a sole-practitioner is likely to make your environmental impact quite minimal. THe worst general chemical is used fixer as it contains a fair amount of silver - but even that is tiny compared to the amount of toxic waste produced so we can wear jeans/ eat sugar/ drive cars/ store food/ live a western lifestyle (the moralities of such is for a wholly different discussion
).
Selenium toner is fine provided you use it to exhaustion (it, not you). I've heard it then makes good plant fertilizer (although probably best to keep it off the vegetable patch).
There is all that about being able to collect the silver from used fixer and sell it back to the industry ... but I dont know of anyone who actually does that (?).
I use my chems until they no longer work. I mixed used developers with used stop bath to roughly neurtralise the pH then pour away. I pour away fixer, then feel bad about it. And I do the same with toners, once they've exhausted.
As for chemical types ... I mix my own film developers, I use ilford bromophen as a standard print developer, harman cooltone (no longer available) and harman warmtone print devs for special applications, for film I use no stop and for prints I use very week ilford stop bath, and for fixer I use whatever I can buy a 5 litre bottle of - usually ilford rapid fix or hypam.
I use open trays for the prints - I like to see what's happening to the print so the slot processors are no good for me. I use a nova slot-washer for washing.