I believe that a home visit should be really necessary and justified. In other words, I would visit a child and his/her parents only if I find it absolutely necessary. In case a child has some difficulties at school in terms of learning progress or relationships with classmates or teachers, I will definitely do a home visit to make sure that parents are aware of those problems and are going to take some measures.
My concerns would be related to the environment in the family and readiness of other family members including older members, parents, and older siblings, if any, to help the child overcome his/her problems. I think that I should not come if I do not know what to tell those people. However, I can get prepared for the home visit and bear in mind a few most important questions to ask such as whether the child experiences some problems with his/her relatives or those problems appear at school only; I will ask if they know about the child’s problems, and what measures they are going to take, if any.
I think the visit will be successful if I show the child’s parents that I am not going to be a teacher in their house and that this is just a goodwill visit; I should not advise them what to do if they do not ask. As I am a guest in a house, I should be polite and friendly because any hostility or bias can destroy relations that did not even begin.