I finally gave up! Every time the girls go near the dollhouse, I’m screaming at them to not touch it so I guess it really is mine after all.
Today I managed to get the things hammered together. DD2 really wanted to help so I let her do some sanding.
Although they are not finished, the girls can already play with them. They dug out a box of furniture that came with the original house and started to set up. The neighbourhood kids joined in too- even the boys.