Part of the art world is driven by speculation. People buy it because they believe that it will increase in value. Believe it or not, art can be included as a “non-traditional” part of a self directed retirement account. Here in the USA referred to as an IRA. Supposedly in this case artistic appreciation of the artwork is secondary. For this to work, the investment must be liquid. There must be a ready market for the artwork when the owner wants to sell it.
I doubt if model ships, regardless of who built them have or will ever reach the point where they will have offer the liquidity to be a good investment.
Roger