Trap and Drain on a shower base in basement

So I'm not a plumber, just an Electrician lol.
We are finishing our basement, the floor is finished concrete. Plan is to get one of those shower kits that includes the base and walls etc. The basement has the shower pipe roughed in through the slab, its not in a great spot since its 4 " off the finished exterior wall.

My question is... how much clearance are under these bases usually?
Is there a way to do a trap as well without out having to open up the floor?

I'm open to solutions at this point

 

Turns out they did rough in a trap Will just have to move the drain that is so close to a wall