It is very true that "having Master Ou's books and calligraphy just like having Master Ou who is benevolent and friendly with us together, and he always cares about us, gives us love, and helps us live happier and healthier." I have the same feeling as you.
It is such a treasure that you have been owing and appreciating Master Ou's calligraphy in the past 18 years! I am so happy for you. To my understanding, his qigong calligraphy gives receivers everlasting beneficial effects according to their needs automatically. Its Qi (energy) field is extremely strong, extensive, and positive. It can promote the positive attributes of many things, and, when a receiver's own energy field gets better by doing more PGSG practices and acting according to the maxim, he or she will have greater achievements.
Thereafter, when we buy a qigong calligraphy from Master Ou, we actually receive a great gift from him. It is priceless!
I will treasure it more by engaging more effort on doing the Six Practices (practicing PGSG daily, studing PGSG theory, healing others using PGSG, guiding people to learn PGSG, following the maxim to conduct myself, and practicing music therapy).