I'd be more worried about the corporate and state actors in your case. A criminal would have to already have intimate access to your home to snatch your video feed, so I wouldn't worry about that. If you do find a way to encrypt the video before saving to the HDD, that would protect you against police or insurance companies viewing the footage without your key.

ETA: Though, NOT providing the key may give them reason to believe you have something to hide and pit them against you. 🤷