bava metzia pg 47b to 48a.

I noticed the answer of the Or Sameach who tries to answer the question on the Rambam chapter 6 law 10 of Meila. The Or Sameach rightly sees that the Rambam never mention meila in terms of change of domain. He brings it only concerning gaining benefit of hekdesh or damaging the value of hekdeh. Thus, when the Rambam says a Jew that buys an object from another Jew with money of hekdesh, but does not pick up the object, he does not commit meila, that is because the Jew’s acquisition is not valid since the sages held that money acquires from the law of the Torah, but there is a decree that one also needs to pick up the acquired object. The problem with this answer is that it should applies as well to the case where a Jew buys from a gentile, which it does not. Therefore, you have to say that the Rambam depended on the the Mishna (and braita) that say if one uses money of hekdesh to gain entrance to a bathhouse, he transgresses meila. Rava said that is a proof to Reish Lakish, but only because of how Rav explained them. But R Yochanan can simply say that braita is just one example of how one can transgress meila. That is by using money of hekesh to pay a gentile.