Yes and no. You have option to hire 6 of them, starting at 200K, next one is double and so on.
Here is price list:
1. 200K
2. 400K
3. 800K
4. 1.6M
5. 3.2M
6. 6.4M
Some crazy people do have all 6, but there is no really big need, as with 5 you can cover (almost) everything. There are 3 different buffs, magic, battle and protection, and you can craft and cook. (thus 5 HK). Sixth, optional one can be kept low level to produce food that increase damage, but it has no food for mage. As it works as storage, there is a good reason to get them (and does not count as another piece of furniture if you get storage chest), and all of them usually sooner or later will get into crafting, one to 100 rest to 80. Usually I end up with more pots then I can use, and it's nice to have some pots, like Galloping one. They takes very long time to level, so sooner you start - better.
How they would set them to work