Who is Damu Anna as introduced in Chapter 25, and why is his story being told?

Chapter 25 introduces Damu Anna as a "well-to-do person from Ahmednagar" who was a wealthy Kasar (bronze-smith) by trade. More importantly, he is described as a great devotee who was devoted to Sai's feet. The chapter sets up his narrative as a prime example of Sai's love for His devotees. The author presents his story to demonstrate how Sai wards off the misfortunes of those who have one-pointed faith in Him. As mentioned in Chapter 25, though the story is short, listening to it is intended to fill the listener's heart with joy and show how the "Guru-Mother is an 'Ocean of Mercy,'" ultimately causing their own difficulties to vanish.