[Trying to explain a modern Christian's stance on slavery, in relation to the OT]
We have man-servant and hand-maids to this day. We purchase them through paying for them and they become part of your "property" as they handle your property. Obviously your own property you handle with care and delicacy, be no different. The only reason why "property" sounds degrading is because its considered "politically incorrect". Also, these settlers as the Bible called some of them, needed work so the work was given to them and usually they stayed and became part of the family. To this day many servants and maids stay in the family even if a original "owner" passes away, as the servant becomes part of the family. A servant doesn't have to just take care of the house a servant could also become an apprentice for a blacksmith.

In referring to your second question, if you are in the market for servants this yes treating them good and all this would apply to you. If you aren't then it doesn't. In a sense it still does but you do not have to think about it as you aren't taking care of one.