The first rule is definitely location. It really is hard to find cheap land in an urban area which has already grown tremendously. However, this does not mean that you go for a land which has is located in a location without a great deal as good road access. It's all about taking your time and energy and finding the right listing with cheap land on the market that is conveniently located. At the very least, make sure the land you are interested in is within a location that is likely to grow. Also think about the geography with the area, and the climate. If it gets too hot or freezing in some seasons, it might not be a worthy purchase, more so if you plan on building in the land.
Second factor to take into consideration is the profitability associated with a cheap farm or hunting land on the market. While land is hardly recognized to depreciate, normally it takes time before it comes from any profit. You have to find land in an area that is likely to grow, because growth will be associated with a land price increase. Even though you don't plan to sell immediately, it is comforting to know that you can get good profit from selling the cheap land for sale that you spend money on.
Stick with proven markets, instead of buying some cheap farm land accessible in an area which is hardly known. This doesn't make much sense when you purchase a piece of land outside in the country, in which you know decades will pass prior to the area ever grows. Instead, buy land in an area that already has a spark for growth, before other people seize the ability.
When buying cheap land available, keep in mind that the vendor will have a sales hype ready, and will try to get you to buy the parcel. But take the time and look at the buying decision. For those who have any doubts, don't ignore them. Regardless, you can always look somewhere else.