Status of the mihraab, mimbar and minaarat

Q: We are building a Masjid and would like to know how many steps did the Mimbar of Nabi (sallallahu alaihi wasallam) have. 

I have read that it had 3 steps in total (including the seat). Nabi (sallallahu alaihi wasallam) sat on the third and stood on the second. 

However, the famous Hadith of Ramadan states to the effect that Nabi (sallallahu alaihi wasallam) ascended three steps and said Aameen on each step, which would imply there were 3 steps excluding the seat, which is 4 steps in total. 

Can you please explain and clarify the above to me.

Q: I am intending to place a minbar on the left side of the mihrab as it is difficult for the khateeb to see the audience if placed on the right, is this against sunnah or is there any problem with this?

Q: I would like to know the status of the mihraab in a Masjid?