So-called alternative investments don't make sense for the vast majority of retail investors, who would be better suited to a portfolio of mainstream assets.

However, there's something rather alluring about alternatives and how they behave from an investment perspective.

Where any of our clients express an interest in investing in classic cars, wine, art, luxury watches or even a stamp collection, we urge caution, explain the risks (and costs) involved, and encourage treating the portfolio as a hobby/passion first, investment second.

This research from private bank Coutts shows it was a mixed year for the investment performance of alternatives last year, with classic cars and fine art falling in value, but rare musical instruments and photography recording positive returns.

One problem with the average performance figures of alternatives is basing them on what is a relatively small and illiquid market; you can't view classic car price changes in the same way as those applied a major stock market index. 

Where alternatives do appeal to investors, buy them because you know and love the asset in the first instance. Be prepared to hold them for very long periods of time. And don't invest more than you can afford to lose.