What follows is an outline of five cash purchases I'm considering as speculative investments. Each will include some of the reasoning behind the picks and some basic rules to follow if the purchase gets made.
The Event Deck Play
The first purchase is one Sigmund brought to my attention here. The M13 event deck: Repeat Performance. Buying these individually for 23$ or less seems like a good deal. I like both for 30$ better. The highlights of Repeat performance include a single Thragtusk, two Razorverge Thickets, a Blade Splicer and a Geist-Honored Monk. That reads to me like a blue chip standard rare, two blue chip modern rares and two more red chip rares. Buying both M13 event decks for thirty means an extra 5$ gets you a Darkslick Shores, two Slagstorms, and a full playset of Dismembers.
Anyone considering these deals need to be able to move Thragtusk or be willing to flip to a dealer at $14. Presently, Thragtusk remains a very popular card despite its inclusion in this M13 Deck and the latest RTR event deck. While the price resilience looks surprising at first glance, a quick look at competitive Standard decklists gives a good reason for the card's current evaluation. The biggest risk this purchase presents a buyer is obtaining the necessary Thragtusk valuation.
Modern staples Razorverge Thicket and Darkslick Shores give buyers a margin of safety. While Modern cards are approaching seasonal lows, a late December rise in values should make turning a profit pretty easy with these purchases. Blade Splicer and Slagstorm give you two borderline playable cards that are easy to move. As long as Lingering Souls is being played, there will be a market for Geist-Honored Monk.
Next couple of purchases will target individual cards. First up, Blinkmoth Nexus. This card is the backbone of any Infect deck and that ability is too powerful to not see play. Any purchase at $4 should turn black in 45 days. TCG has a few NM copies at this price as I write this article and while Ebay pricing is moving higher already, there are still some to be had around the $4 target. The card saw enough play while in Standard that trading to pick up copies is an option. For that reason, be very frugal with your cash and look to buy only at $4.
Blackcleave Cliffs is a great Modern target at $4.50 or less. Both Ebay and TCG have multiple copies listed around $4 in NM condition. B/R will form the backbone of many a competitive Modern deck. Of every Magic format, Modern has the most room to grow. I expect that as the format gets more tournament support, the cards in the format will see a big rise in valuation. Much like Legacy before it, Modern should put in a higher floor for staples. The easiest way to position oneself for that kind of movement is to get a hold of some real estate in the form of lands. The larger the format, the more the broader demand for lands benefits you. Instead of figuring out the next hot piece to a deck, enjoy the safety of fastlands. Their inclusion is almost automatic, assuming the deck runs the appropriate colors.
Next up... another land. River of Tears is selling for less than 2$ all over the place. This card should at least get to today's prices for Darkslick Shores as its drawback is easy enough to play around early. Considering how many Darkslick Shores and other Scars lands are still in binders, I find the pricing of River of Tears a bit ridiculous. Maybe no one remembers playing with it? I am very interested in picking these up at around $ 1.80, as I expect they'll climb to around $3 in short order.
Finally, a card with a home outside of Modern: Phantasmal Image. This card at $5 is worth a look. It functions as a lord, making it a 4-of in any Merfolk deck. For 2cc you can copy hexproof creatures, kill legends and either trigger enter the battlefield effects or replicate those effects. This card is played in Legacy, and with Simic promising more Merfolk has a good chance to become a regular in Modern. At 2cc, even Legacy can't ignore Phantasmal Image. While it is hard to find this guy for less than 4.5$, a quick survey of TCG prices suggests that even stores are not sure how to value this guy. Playing that spread when trading for Phantasmal Image makes him a great trade target too.
There are plenty of cheap, readily available Modern targets. Most should be acquired through trade (see Phyrexian Metamorph, Birthing Pod, Elesh Norn, Grand Cenobite). When surveying the field of Magic formats ask yourself what is over-hyped/over-valued and look to trade out. Trading away from hype and into value will help you unlock value and let you both flip cards quickly AND maintain an inventory of growth plays. Buying into M13 event decks, looking to trade Thragtusk at TCG mid prices for future Modern Staples, will maximize your dollar.