I got the LEGO® London Bus set 384 when it first came out around 1973 or 1974. I don’t recall how much it cost, but I am sure it was less than $10 or so. If new and in mint condition with the box still in plastic, it should be worth somewhere between $500 to $600. Not bad for a 43 year old set! This is about 9% to 10% increase per year! This is almost in par with S&P 500 growth for the same time period. Granted, what child in the 1970’s would have opted for keeping this set in the box instead of opening it and having years of fun. That is what I did. Nevertheless, it would have been a sound LEGO® investment.
It has on display since then. This is one of the easiest sets to build, and in my opinion, one of the nicest. The set inventory and build instructions are available through several sites including Toysperiod.
Here are few photos I took for this post.