Sorry I was looking at the sketch with a fish room. Either way a shower isn't hard. Is it all roughed in? Pee trap installed already for the shower?
I'm not sure about the reinforced steel, my basement is walk out and that wasn't the the case with me. On the plus side walk outs are perfect for getting large sheet of drywall in
My basement is in the works as well, at the stage drywall is all done and primed. I have record of all the expenses if you're interested I can post more details.