Would I be considered disobedient to my mother if she rejects the location of the land I bought and I insist on it despite my potential loss and my inability to buy in the location she wants?

If the matter is as mentioned, then the questioner is not obligated to comply with his mother's wishes for the following reasons: First, he would incur a financial loss that he cannot bear, and the rule is "there should be no harm or reciprocating harm." Second, he may not be able to purchase a plot of land in the place his mother desires, and Allah the Exalted says: (Allah does not charge a soul except [with that within] its capacity). Third, he knows more about business matters and what usually achieves benefit outside the home, and the mother does not have the right to obligate him with such matters. To follow the best path, he should treat his mother well and strive to convince her of his point of view, and send to her someone he trusts and she takes advice from, while being kind to her and supplicating for her righteousness.