Plumbing costs

What neighborhood is this in?

Are you dealing with a contractor or plumber directly? If former, the contractor needs to make some profit. Find a plumber who works for himself. It will be much less. Moving gas line may be time consuming due to safety regs.

We are working with a contractor and the the charge for the plumbing is itemized in the breakdown of costs.

That explains it. Contractor needs to make some money.

Will they be re-piping all the way from the risers? It's a good time to make sure you have shut offs for everything individually.

They will but the building takes care of that. We actually have to pay a fee to have all the water shut down to the apartments in our line.

So if the building takes care of that I would just make sure the contractor is not charging you for that portion of the job.

The building shuts down the water in your building so your plumber can install your shutoff valves. Once he does that he should change all the branch lines back to the riser. $7k for the plumbing in the kitchen seems very high. Can I ask how much you are paying for the kitchen? There are different kinds of contractors just as there different kinds of everything. If you buy a Porsche it will cost a lot more then Honda. I used to use plumbers that cost $1,200 for a kitchen. Now the plumbers I use for a kitchen cost 4-5k. It costs me more because they are so much more professional in every way and it turns out it is very much worth it.

But how do I know that I am not paying $6500 for a 1,200 plumber? I have no ideas whether they are professional and reliable and will do a good job. I suspect that the contractor is pocketing half so it is likely that they are so, so for $3000.

It sounds like you don't trust your contractor which is not good to begin with. In theory you should be able to trust your contractor and not really worry about what plumber and electrician he or she uses. It is his responsibility to make sure you get what you pay for. For the amount you are paying for the service should be excellent,

Enough with the plumbing already. Call a reputable plumber or contractor. There was a lady on here before who got obsessed with her toilet seat ... just too much and not necessary for Streeteasy. Enough.