I recently read a booklet called "Wolmar Schildt — sata uudissanaa" which is built around a list of a hundred neologisms by Wolmar Schildt (1810–1893), one of the most active promoters of Finnish language of his era. Among these neologisms (in addition to the word "neologism" itself, "uudissana") is the verb "sisustaa". Translations are provided to a couple of languages, and in English it is aptly rendered as "furnish", in the sense of placing furniture in an apartment.
The Latin translation provided is instruere, but I'm not convinced. Lewis and Short give "furnish" in the sense of preparation, not in the sense of interior decoration, unless I'm mistaken. Is there a classical Latin verb (perhaps supported by a noun or two) for furnishing which is attested in the sense of interior decoration or acquisition of furniture?