@NCperson is correct. To claim the credit, the taxpayer must use the home as a residence.
Interestingly, the taxpayer does not have to own the home, or even be a borrower on the mortgage to claim the credit. But they must use the home as a residence (as well as pay for the system, of course). It does not have to be their main residence or their only residence, but it must be "a" residence of the taxpayer who claims the credit.
This requirement is not changed or updated by the Inflation Reduction Act.
