I didn't feel like it was invasive because I had prepared to bare my soul. I was actually pretty surprised in some areas that they didn't dig deeper into things. But then again, there were some things that I didn't really expect and hadn't prepared for - mostly areas where my husband and I hadn't discussed earlier enough to come to a decision about (for example, how strict or lenient will we be with a child if they don't some of our strong beliefs).
And the way we did it was foster-adopt, so a lot of stuff came out during the training and I didn't even realize it was part of the home study until later. So mostly it felt very comfortable and not at all invasive. Ovbiously, things like talking about our own childhood abuse or neglect is going to feel invasive no matter what - but you can understand why they ask and of course that's going to differ for each individual.
As far as the home visit, I was amazed they didn't want a cleaner, more organized perfect home. They were really just looking for safety stuff like working fire extinguishers, windows that open, clear pathways from room to room, working plumbing, etc. And then randomly they'd open cupboards and closets to peek around. We had to make a few adjustments (get a fire ladder for upstairs, larger fire extinguishers, etc.) and then we were approved. There are also specific rules about pets and where they can eat that we had to adjust (an old weird rule that pets can't eat in the kitchen).
Here is a list of most of the documents we were required to share. That gives you an example of the areas where they start digging. They will want you to explain any therapy or criminal history, that sort of thing. Obviously, the less of that you have the easier and less invasive it feels.
Copy of Marriage Certificate (if applicable)
Copy of all Divorce Decrees (if applicable)
Copy of Death certificates (for former spouse, if applicable)
Name, Address and Phone Numbers of all Therapists/Counselors (if applicable)
Letter of Explanation for all Therapist/Counselors (if applicable)
Previous year’s tax return
Copy of Bankruptcy Discharge (if applicable)
Physical Exam by an MD
Court records (if either applicant has criminal history)
Explanation of criminal history (if applicable)
Child Support Orders (if applicable)
Pet vaccine records
References from friends