hydronic floor water heater cost

Hi,
I just bought an Eicher (in MountainView, CA) and surprise surprise the water heater for the floor heating system has a massive leak (inside the heater itself) and needs replacing. I got a professional to come onsite and the quote given was ~$10k for the equipment and installation. I got a second quote from another company with the same value. Taking into account the amount of work involved and equipment this seems excessive.
Could anyone educate me on why this is so expensive and/or give me any other hints?
 
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