Fair quote for tankless install?

Called a plumber in my family & friends network for a quote to install a new tankless system. 3br/2ba condo in Chicago currently operating off a ~10 year old tank system which still works fine, but we want to better utilize space in our utility room.

Quote shown here is $6250 including the Navient unit and installation.

I see that the Navient unit listed retails for around $1500-1800…is it typical for the install to cost 2-3x the price of the actual unit?

I was told that “no plumber worth his salt” would install a unit that he didn’t sell me (at a nice markup!). Is this true?

Appreciate the wisdom of this group!

Called a plumber in my family & friends network for a quote to install a new tankless system. 3br/2ba condo in Chicago currently operating off a ~10 year old tank system which still works fine, but we want to better utilize space in our utility room.

Quote shown here is $6250 including the Navient unit and installation.

I see that the Navient unit listed retails for around $1500-1800…is it typical for the install to cost 2-3x the price of the actual unit?

I was told that “no plumber worth his salt” would install a unit that he didn’t sell me (at a nice markup!). Is this true?

Appreciate the wisdom of this group!