(Mishnah): If a husband spent money to upkeep his wife's property, whether he spent much and ate little, or spent little and ate much, what he ate he ate (there is no compensation);

If he spent and did not eat, he swears how much he spent and receives this.

(Gemara - R. Ba citing R. Chiyah bar Ashi): Even if he ate only a basket of dry figs [there is no compensation].

(Asi): This is if the expenditures exceeds the Shevach (improvements), but if the Shevach exceeds the expenditures, we give to him the Shevach.

Question (against Asi - Tosefta 8:3): All of them (one who spent money on the property of his wife or of a captive), we estimate for them like a sharecropper.

Answer: The Beraisa discusses saplings. Rav Asi discusses building (all the improvements are due to his expenditures).

Question: [Can you say that] the Beraisa discuss saplings?! Did not R. Ba citing R. Chiya bar Ashi say 'even if he ate only a basket of dry figs'?! (Even for trees, he does not get like a sharecropper!)

Answer: Here (even if he ate figs, he does not get more) is when he ate. Here (he gets like a sharecropper) is when he did not eat.