As long as you don't expect to get your money back if you do move it on eventually, there is no real harm in restoring an unpopular pinball machine. After all, it is a hobby first (yes, hobbies do cost money, some more than others!). Some people spend time and money doing up cars, some people spend time and money slotting coins into a poker machine, and so on. Purchasing a pinball machine as an investment is very low on most people's list, although admittedly most people would like to be able to at least get their money back if they do sell.
