I am confused by the similarity of this sentence to another, both of which have the feminine subject "near" someplace. This one has the feminine noun, casa, and feminine adjective, vicina. The other, "La scala è vicino l'entrata," also has a feminine noun, scala, but it is paired with the masculine adjective, vicino. Help?
The trick is that in the latter vicino isn't an adjective, but an adverb :) Just to make matters more complicated, it can be a noun too! (neighbor) You can usually distinguish with what follows, as the adjective raises the question near to what? (so it's usually followed by the preposition 'a'), while the adverb near where? (so it's usually followed by the place). You can guess when there is nothing after it: "la meta è vicina" (the goal is near), "è qui vicino" (it's close to here).