Been playing Marapets for 17 years and I've never once attempted to form a treasure map... until now! I decided to go for the Sewer Pipes Treasure Map.

2 - got from AU shop
3 - 1m + instrument
4 - got from AU shop
7 - 1m + instrument
12 - got from AU shop
13 - 1m + instrument
14 - 9m + plushie worth 450k
15 - got from AU shop
16 - got from AU shop

I got an extra piece 15 from the AU shop and I sold it for 4.9m. So far, I've spent 10 AU and 7.1m MPs. I still need pieces 1, 5, 6, 8, 9, 10, 11, which will cost me approximately 44m MPs.