re: Can I secede my property and create my own country?

"Hello China, I've got something that you want. But it's gonna cost you. That's right, all the tea."

Hum... you might be able to form another state with your land; and your best bet to do that would be if you owned land in Louisiana. We have some of the strongest personal property rights in the nation - under Louisiana law you own a wedge of the earth going to the core (essentially). So the state has no claim on your property directly (unlike other states wherein the state owns certain elements of the land below ground - oil, precious metals, water rights). However, the state does possess the right to tax the production of your property... so maybe if you offered enough cash to get them to leave you alone then you might could pull it off.

Most state related property disputes are about which state owns or controls said property. I'm unaware of a US Supreme Court ruling concerning the formation of a new state from the property of another.

Now, as to forming your own nation. Suppose the US or your state didn't care enough to fight you (send in military/police), you'd still need to be recognized by a permanent member of the UN or a majority of UN members in order to be formally recognized as an independent nation. That's a pretty big hurdle.

That being said... the USSC still hasn't decided whether or not a state can secede. Jefferson Davis requested many times to be tried for his "crimes" but he never was. He wanted his day in court which would force the courts to decided the legality of secession. The Supreme Court at the time likely would've ruled in the South's favor - that's why Lincoln and Grant did everything in their power to avoid post-war trials (pardons and whatnot).