1.it is not easy to explain 贪图 and 省事 respectively, 贪图省事 means he takes an easy way out because he doesn't want to be tired.
2.No , not antonyms. 撒 can be regard as a verb in English while 入 should be a preposition, 撒入 can be translated into "cast in"
3.竟 means "surprisingly" and "unexpectedly". 拉 is "pull" 翻 is "make sth reverse"
4.贪得无厌 means greedy and Insatiable.