I think he's asking way too much. I'd spend my money on something else. Chrome has been around forever, brushed nickel will come and go.

Chrome is usually cheaper, but not that much different. He may be trying to pad his profit. Or it may be a better quality faucet if one is basic builder grade and the other is a different model. See if you can get an allowance for the basic one and supply your own in whatever finish you want.

BN is usually a 30% up charge over chrome. Then add in the builders 20% on top of that. For an average decent quality but still builder grade $150 lavatory faucet, upgrading to brushed nickel would add under $100. Now, if the spec is a more upscale $300 faucet, we'd be closer to $200 in difference. He might also be charging an administrative fee for change orders, so that could factor into it. Or, if the faucets are already installed, $200 per is more than reasonable for the cost difference, and the time of the plumber to change them out.

You would pay more than that yourself later to have it done, as you'd pay for new faucets and plumbing labor. Which is what he is counting on as motivation to do it now.

What finish is in the shower and tub in both the secondary? I assume builder standard of chrome? Unless changing all fixtures in a bath,, I'd leave it at chrome. If you are including those in a 200.00 upgraded selection for each of the baths..........? Pretty darn cheap if that is what you want and it considers double sinks, diverter, tub filler etc. I think chrome is a better selection, frankly.