Thank you guys! I feel more confident now. Giving him supplies for cleaning and laundering is what I would do, because I have enough Tide to last me for several years so that would be his detergent, and I make my own vinegar+dish-washing liquid+drops of lavender essential oil solution for a spray cleaner, and buy paper towels at Costco, so the marginal cost for me of providing him with the supplies is very small, but the gesture would be appreciated. I won't clean his bathroom though. I will draw the boundary at my providing him with the supplies and the laundry room key.

Inviting him to share a meal once or twice casually without sounding overbearing is another thing I will do, and yes, will leave space for him in the fridge and on kitchen counters. I buy a gallon of milk each time I get milk and might just tell him that he is welcome to use it as a creamer for his coffee since it is not much quantity anyway. I won't offer other foods or liquids from my fridge, so the boundary will be drawn there.

This is beginning to sound exciting even! Most importantly, the guy is laid back and low key. Very casual and down to earth. I think it is a good trait. He is the kind of person to who it is easy to say: "Hey, this and that, not that it is a big thing, but I wanted to mention that..."