We have 2 wall mount toilets in our house that we want to replace. I know that it is going to involve a lot of work in order to remove the wall mount units. Our basement bathroom is right below one of the upper bathrooms. This lower bathroom is gutted right now because of a flood last winter from up stairs. There is a 3" copper drain pipe/vent that runs to the upper bathroom wall mount toilet. We want to replace that toilet with a floor mount.

Now I've got 2 questions about this.
1. How much work is involved with ripping out and replacing the toilet? The water source is not going to move for the toilet. Would just be moving the drain from the wall to floor. Am not worried about the dry wall and floor up stairs yet, going to remodel that bathroom later.

2. We might also split the upper stairs bathroom into 2 and make a 1/2 bath. How far away from the first toilet can the second be and still use the same vent? I know the plumbing needs to drop 1/8" for each linear foot.

We had a plumbing company give us a bid for this work and quoted us about 7000.00. I thought this was way out of line for about 10-15 hours worth of work.