Inkwartiering means billeting, when soldiers were quartered in civilian houses. This could happen during times of occupation. Town records may have lists of houses where soldiers were billeted, including compensation for expenses.
Knowing your ancestors had soldiers billeted at their house can be useful in different ways. Apart from being an interesting piece of biographical information, it places your ancestor in a specific time and place, which can help to determine when they died or moved, for example. It can also tell you about their economic situation, in comparison to their neighbors. A person who had twenty soldiers billeted at their house at once did not live in a hovel. If they were compensated for billeted horses as well as soldiers, that means their house had a barn or stables for animals.