Bricklink has this handy feature on its site which allows you to view the average selling prices of a particular set based on previous auctions.
I like this feature, but unfortunately, it only displays trades made in the last six months.
Are there any tools that can track or display historical selling prices on sets. Preferably using data from popular LEGO auction sites like Ebay and Bricklink.
Yes, you can see the price development of sets on the Brickfact website. The prices are calculated daily by sales on Ebay and Bricklink.
If you want to keep track of the price development of all your LEGO sets you can you use the Brickfact portfolio tracking app. You can enter all your sets there and see the individual price development as well as for each of your sets.
Not sure about several years, but Brickpicker covers one full year. Here are the stats for the Green Grocer, for example:
Or the ones for the UCS Millenium Falcon:
And so on, you get the idea. They have more and other stats, too — e.g. the following quick overview for every set:
They pull their data from eBay, through some third-party tool they licensed.
Now, I think they only let you look up like three sets at a time — then you have to register. But the registration is completely free. They cover their costs via affiliate marketing, i.e. links to Amazon and the like.
They can also sync your account with (i.e. import your sets from) Brickset and Rebrickable, but I never gave that a try. I'm not much of an investor anyway, just your typical AFOL. In fact, according to them, the prices for some of the discontinued sets I still have unopened have actually plummeted.
I suppose if I were in for the long haul, I would just take a screenshot of their stats every twelve months and then string them together in GIMP.
I'm not familiar with any tools that do this with eBay or Bricklink price histories. I'm pretty sure that Bricklink removes all data older than 6 months, so if this information is available, it would have to come from a third party who scraped it from the site.
I have used a tool called Tracktor to look at Amazon price histories for LEGO sets. Sadly, this tool is most useful for sets that are currently in production, as there aren't many listings for out of production sets on Amazon. Here's an example showing the price of Medieval Market Village (10193) over the past couple of years:
