Except that, in all fairness, was it built with their prior approval? If not, I am not sure we can legitimately ask.
I know of someone older (in their 80’s) who decided to invest his own $$ to upgrade a kitchen in a rental apt. When he moved, he asked the property owner to reimburse him. Landlord said: get lost, you never got our permission to do the work, so we’re not paying.
I hope then that the gentleman took the appliances with him and replaced them with old cheap used ones matching the old ones that were there.