Hello Trent,
Who has placed the advert? Estate agent? It would be very risky to buy any plot of land that is not already classed as "urban" on the strength of what it says in an advert. You or your lawyer MUST verify 100% for yourself the claim re any plan to urbanize the area. Until then, the land is no doubt rustic and so the price should reflect this and you would not be able to build on it.
The "land grab" problem in Andalusia is not so much of one as in Valencia but cannot be ruled out until your land is reclassified, legally.
See you soon