I have a suggestion!
As a pet sitter I've dealt with people just like your SO, and I totally get where he's coming from. Here's a few things you could do that might put him at ease:
-get key locks for your bedroom, home office, or other rooms with valuable things. (I've had two different clients do this and it doesn't bother me one bit. If it makes them more comfortable I'm all for it!)
-Call your vet (who you hopefully trust) for a recommendation. Most vets will have at least one sitter they know well and can suggest.
-Make sure the sitter is bonded, or has insurance. You can also ask if they've had a background check done. I'm currently going through the process of 'making things official' and one reason is because I've had a few different people ask about back ground checks.
-Ask the sitter to come meet you ahead of time. I always do a free visit so the owner can meet me, introduce me to their pets, and feel safe allowing me into their home. An understanding sitter should have no problem with this.
-Ask if you can pay with a post-dated check. I have about 3 clients (2 of whom are the door lockers
) who always leave me a check dated for the day after they come home. This way I feel safe knowing I have a check, and I'm sure it helps their peace of mind as well.
TBH I think its best for cats to stay home and have someone come see them. Kitties are such homebodies that kenneling anywhere can be way too stressful and can cause medical issues. yes, I'm a bit biased, since I do home visit pet sitting...but I wouldn't kennel my own cats either!
Do you have a co-worker who has cats that you might trust? You could offer to trade pet sitting now for you doing the same for them later???