Is ownership a MUST for subsidies?

Hello

My husband and I, as well as his sister and her husband, want to move into the parental home (who still live there).

Parents live downstairs.

Sister and husband want to renovate/convert the upstairs.

And we want to completely renovate/convert the annex.

We are now considering, the sister won't get financing if she is not listed in the land register, we would have no problem if the parents transfer the entire house to her and give us lifelong right of residence.

We want to use, for example, pellet heating and solar technology, both of which are subsidized. In the meantime, one can also claim craft services for tax purposes. Theoretically, we could also save money.

Can these subsidies and tax benefits also be used if you are not the owner but only have lifelong right of residence, which of course should be anchored in the land register?

Or would it be more sensible to divide the house (which would be no problem in terms of surveying) and thus each have "their own house"?

Would be really grateful for tips.

Hello,

in the funding documents of the Wfa, for example, it says "Eigentum," therefore it must belong to you, that is probably an okay criterion.
Furthermore, the Kfw also mentions builders or buyers, therefore it also only concerns ownership here.

Best regards