The kit-and-caboodle of the purchase is a huge financial undertaking that includes not only the desired instrument, but also music lessons, music score purchases, transportation to and from practices or performances, proper recital or performance attire; not to mention any unforeseen incidentals, as well as your personal time away from home or employment. Therefore, one should consider both "long-term", as well as "short-term" goals in answering the question of "expected outcomes" once the investment has "matured".
Both Investor and Investee must take into account their own subjectivities as they consider the possibility that the final investment outcome may end up being in another area due to life choices. Therefore, it is not solely about the instrument's monetary value, but its reciprocal value seen when one participates in a Community Orchestra... Hearing the joy expressed while playing, performing; reminiscing about times past; and seeing the beaming faces of musician and audience member alike. It is this reciprocal value that grows from the love of the instrument, and the impact that music has - from the beginning music student to the "matured" music enthusiast.
Photo: "Kaufhaus des Westens", 1907; Public Domain via Wikimedia Commons.