My suggestion to you is to treat him to a meal to increase your relationship, and you can also make him your friend, because his character is very noble and worth associating with.
The second is public thanks, such as writing a thank-you letter to his unit, or making a thank-you phone call, or sending a banner or something.
In the future, you should go to see him and his family during festivals. If you really can't go, you should call them to say hello.
I recommend you several gifts to repay your kindness:
1. Personalized real-life dolls: Make dolls with your designated head photos, purely handmade, with realistic effects, creative and funny, no deterioration or fading, and can be permanently commemorated.
2. Customized photo gifts: Such as customized mugs, customized photo pillows, and customized photo puzzles, all of which are personalized, ornamental, and practical gifts.
3. Customized greeting chocolates: Write what you want to say to your benefactor on the chocolates. Using raw materials imported from Spain, the cocoa butter has higher purity and tastes more fragrant, soft and smooth. It is purely handmade and made to order.