Or HaChaim on Genesis 24:10/אור החיים על בראשית כ״ד:י׳

1 עשרה גמלים, Ten camels, etc. One reason that Eliezer took ten camels was that relative to Abraham's wealth this was equivalent to an ordinary person taking one single camel loaded with gifts.

2Another reason is that the number ten simply means "many," as we find in Samuel I 1,8, where Elkanan asks Channah if he was not worth more to her than "ten sons?" The meaning there is clearly not the number ten, but "ten" as indicative of a large number.

3The reason the Torah adds that the camels belonged to his master (something we would have assumed even without it being mentioned) is that these camels were specially trained to answer Abraham's specific needs. They were capable of carrying especially heavy loads.

4The Torah adds: וכל טוב אדוניו, "and all the good things of his master," to tell us that Eliezer took the choicest of all the precious possessions of Abraham. This was in order to persuade the girl in the event that she would initially refuse to move away from her parental home. Seeing that her husband-to-be possessed such wealth might change her mind. The word בידו means the same as שבידו, something that was under Eliezer's control (inasmuch as he was in charge of all of Abraham's possessions).