What happened when Baba sent a message asking for fifteen rupees Dakshina from Shama, and how did Shama respond?

In a surprising event detailed in Chapter 18, Sai Baba sent Madhavrao to Shama (the author) with a specific message. The message was to collect fifteen rupees as Dakshina from him. Baba also instructed Madhavrao to sit and talk with Shama for a while before they both returned to the Masjid. Upon hearing this request, Shama was 'extremely surprised.' Instead of providing the fifteen rupees in cash, he offered a different form of payment. He told Madhavrao to convey his 'namaskar' to Baba as his form of Dakshina. Madhavrao accepted this, noting that fifteen namaskars were received, and then urged Shama to begin telling stories as Baba had instructed them to talk.