<prompt> Human: I know this could be up to debate forever and the situation differs from person to person. Im really torn right now between options with my own situation and would love to hear some of your opinionssuggestionscomments. Eventually Ill make my own decision of course.About me: 36, work in finance in nyc, unmarried but in a stable relationship. No pets, no kids, no school loans, no other debts except mortgage below. Im a saver and manage my finance pretty well. Investment: ive been maximizing my annual 401k and Roth IRA contributions for a few years now and will continue to do so. No other brokerage investment accounts given my jobs regulatory limitation.Property: i bought my first ever home in nyc 4 months ago, put 35 down payment and get a mortgage over half million. i locked in a 30-year fix mortgage rate of 3.375 at the best timing last year VERY happy. The home is a new condo with NY 421-a tax abatement, so property tax for the first 10 years is negligible and will go back to normal after 15 years.Current options: i just got my annual bonus and need to make a decision. i think ive set aside enough funds for rainy day fund and travelleisure expenses, and if there is no change my current monthly mortgage payment plus common charges are at a comfortable of my paycheck. There is about 50-75k at my disposal and im a bit torn regarding options below:- prepay my mortgage principal this is roughly like a 3.375 annual return, as my mortgage interest tax deduction is not significant; not a very exciting return rate but it does save me mortgage interest in the long run- explore second investment property a little tricky as i cannot afford another one in nyc area and buying a home in another state involves lots of time, energy, and maintenance, and i have a busy job- other investment opportunities, such as business partnership with friends or family members?- leave it liquid now for future better options? long shot - self start-up etc.- any other good ideas?Thank you for your inputs!  <response>: This is actually a really common question and if you check some sidebarwiki posts there are very thorough answers. 