My husband fixes the tech stuff, I fix everything else, or at least attempt then tell him how to do it. My hands are weak from hurting most of the time. But yeah you need to set down some boundaries. Don't argue. Kill them with kindness. Maybe look up a youtube video for it for him to show him how to fix it. That's how I fix things. Youtube has almost everything. I still need to fix our dishwasher, but I'll get to that hopefully next month when I have some money. I grew up working on stuff so I got that stupid engineers mind and my husband doesn't.