1) The basics: Food, water, and waste disposal. If you're going to secure a piece of land to settle, it has to be able to fulfill the biological needs of those residing upon it. In a place like Syria, this kind of prime real estate will be heavily defended.
2) External security. ISIS is an army and armies have artillery. You can go ahead and hole up in your reservation; nothing is stopping them from dropping mortars on your head except for their limited understanding of trigonometry.
3) Internal security. Let's say you get your land and open your doors to all Syrians seeking safe refuge from the terrors of civil war. Just one question: how do you tell the difference between a refugee and a suicide bomber pretending to be a refugee?
4), 5) & 6): Shelter, electricity, and infrastructure. Unless you're planning on the war being over in a few weeks, you might consider investing in the rudimentary elements of modern civilization. Unless, of course, you think living in tents in the middle of the desert is preferable to asylum in Europe or the United States.
7) Mathematics. If ISIS or any of the other Syrian factions decides they want to do away with your camp, it is unlikely to remain under your control for very long, no matter how much money you dump into defending it. They are mobile, they know the land, and, perhaps most importantly, they outnumber you. By a lot.
8) There's also the ethical concern of occupying land in Syria. Despite the shitstorm brewing there, it remains a sovereign nation with a recognized government. We can't just drop in there and take a slice of Bashar Al-Assad's back yard without stirring a geopolitical hornet's nest.
As shitty as it sounds, I think offering Syrians asylum is the best, safest option.
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