General Power of Attorney

Good Morning. Kindly understand that i have a 0 knowledge and asking in the same pattern I would like to purchase a land of 1000 sq.ya from a vendor who received that property from his mother. I would like to sell that purchased land immediately with some minimal profit. Hence I would like to know what is the best agreement for that. Sale deed is the option which we can do but i will be facing with 6% taxes. As it is only for reselling taking GPA from Vendor and selling the property reduces the tax on me which i feel. But some of them advised that GPA can be changed by vendor at any time with out the consent of me and also it cannot be valid if the executant dies unfortunately. I wonder how the Big Big ventures sell the Property. They also make a agreement with Marketers to sell the property on their behalf. I would like to know how their contracts are made in a safe manner Hence please let me know what are the best ways which i can sell that property by agreement. What is the best way of making an agreement where me & my vendor can be in safer sides. Also describe what are its Positive & negative sides. Kindly help me. Regards N.Avinash