Related for Ketubot 132:7

She agreed to bring in for him money, each sela (=4 dinarim) becomes 6 dinarim [including +1/2 compensation for the use of the money in the meantime]. A groom accepts upon himself [responsibility] for 10 dinars for the perfume fund [for his wife]. (The word "per maneh" is not in the Ehrfurt manuscript.) Said Rabbi Yose: This is the halakhah, a place where the custom is to not reduce from the evaluation and not to add to money, they do not deviate from the local custom.