Hi guys
Lets put some perspective to this thread:
Whilst I respect people speculating when sets will retire, that doesn't mean I buy everything that is mentionted. It doesn't even influence my acquisition model much.
In general I stick to the following buy/sell rules for exclusives (Normal sets, I buy when there's a steep discount at the end of its life):
1. Never buy sets the year they have been released. Unless it's of the "Lego Ideas" / Seasonal collection it's too soon to lock up capital.
=> if you do, you'll have a stock of sets that need at least 3 years before really starting to appreciate. This lifts your working capital to unsustainable level and reduces your RoC. The tumbler therefore is too soon to stock up. It will stay live another 2 years at least unless there's a design flaw.
=> this also reduces the risk of having too many DS, TB (and SSD) for too long for example.
2. Buy the best exclusives released > 2 years ago according to your own evaluation model: this means appreciation potential based on sales, stock, personal preference, regional segmentation, ... This site is full of advise on the matter, so do some reading . I pick all these sets up at a regular rate. Emazers has a very successful system doing so, and I do take his advice in the matter. The 'Macks' also promote this way of buying and show you when and where the discounts are to pick the sets up at the best timing. (like last month for example)
=> There's also ample time to accelerate the buying when sets start to phase out. Regular screening of reseller sites and this one should help improve the timing even more.
3. Buy the exslusives you missed out on after they have retired if you feel they can appreciate. Even though that means you'll miss out on the discount effect, if the sets is really strong, you'll be able to go for the long-term appreciation. The surprise exit of TH might be a, interesting target. It's stats are good and the retirement earlier than expected. (at the same time of GE) You can still get it on BrickLink at a very good price
For info BL at 215E: http://www.bricklink.com/search.asp?pg=1&q=town+hall&sz=10&searchSort=P
4. Buy exclusive rare sets that have very limited stock left but very high collector value. I rarely do this, but had some success in the matter (buying some Marina Bay Sands for example at MSRP +100%) It means you are speculating more money on even more appreciation, so the work to put in and risk analysis is higher. But so are the returns.
For info: http://www.bricklink.com/search.asp?pg=1&q=bay+sands&sz=10&searchSort=P
All these comments are with one final purpose: reduce your working capital and improve the returns on capital. Too many people have too many sets stocked away that are still produced by TLG. They have only limited space, and tend to sell too soon, just to free up space and money to get into another set. This pressures again the CAGR and RoC. Make your business model lean and mean. And be careful when you buy: know when you pull the trigger. Once you have a set, selling it will always be more difficult.
I hope this helps.