PuristSPro is not about money and we try to talk about price as little as possible as it detracts from the collector's experience. On the other hand, FORBES is all about money money money. So I approach this with a balance of collector mentality and yet advisory mentality.
Please note, I'm not a Financial Planner. So no liability here on what is stated.
Wayne Carini is exactly right. Buy vintage Volvos, especially the P1800. Sell vintage Mercedes. I would even say consider selling air-cooled Porsche 911s (they're close to the peak now). Sell vintage Mercedes-Benz vehicles except 300 Gullwings, hold onto those. These will increase in prevalence as MBZ, Tesla, BMW, and Lamborghini create more cars with doors that go up.
I would add... Buy vintage BMWs (values are skyrocketing). And I think it's a good idea to even start buying vintage Audis (the original old QUATTRO cars are historically significant). However, note there aren't many vintage Audis and they don't seem to last very long reliability-wise, also the Audi demographic is not into vintage cars the way BMW and Mercedes-Benz demographic so this is hard to say...
Judith Miller is right, vintage Japanese, Chinese, Korean, and even vintage European porcelains as a whole are increasing in prevalence. The European stuff (Meissen etc.) not so much as the Oriental stuff. Modern European pieces are going down in value. That mid-century modern furniture is at a high right now and prices will stop increasing or increase very slowly from here on out. So it's a good idea to consider selling.
I would add... silver teapots and other beautiful silver housewares stuff is going out of production. Christofle is closing stores, Tiffany & Co. is going to cut production; this stuff is going to become extinct. If you like silver candlesticks, tea services, etc. this will be the last chance to buy new. They'll eventually hit auction where you can buy them very reasonably priced too. That Tiffany & Co. dragon fly tea service is nice. American interpretation of Chinese-Japanese tea pots in Western sizes. A wonderfully odd clash of Westernized interpretation of Oriental stuff.
Robert Parker is right on the money here with the wine. The 2010 Southern Rhone wines, especially from Chateneauf du Pape tasted really young back when they were released, but they have aged OH SO NICELY and they're still reasonably priced. So if you can get 2010 and 2007, get it. Mine have been aging nicely. In fact, I had a case of one of the Chateneauf du Papes and I've enjoyed seeing it age so nicely in just a 3-4 years that I'm down to my last bottle.
I would add... Go for more 2007s, especially Californian 2007s. The 2007 Californian wines seem to be very good, perfect weather that produced great wine. It will be a year long remembered in your cellar. And they're still affordable and for sale at major retail outlets.
John Reardon is more or less on the money here if you're talking about a very short-term outlook.
I would add... From a long-term financial perspective sell sell sell! Vintage Rolexes are still going up but may start plateauing any month now. The only thing I would buy is vintage Langes. The Great Lange watches before Lange started making these crazy thick ostentatious pieces, such as the original Tourbillon Pour Le Merite, the original Lange 1 Tourbillon, Turbograph, the 1815 Moonphase, Langematik Anniversary with enamel dial and red XII, the Richard Lange PLM, up till the Richard Lange Tourbillon PLM. Every super esoteric piece from the Lange 1 Tourbillon Perpetual Calendar and after has been very pretentious, too thick, rushed execution, etc. The Lange with the star chart on the back screams neavou riche, superficial tastes, and isn't half as nice as the Patek Philippe Celestial. Lange is expanding its factory too, so don't be surprised if it becomes more mainstream.