Song mainly in Bb (A#). Other stanzas are same with slight variation within the Bb octave. I'm not too confident about the third chord, I've used Ab, I could be wrong.

To my saye ;)

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Song: Kase Sartil Saye (OST)
Album: Divas Ase Ki (marathi)
Singer: Salil Kulkarni

Suffix '1'- indicates note from next octave and '0' from previous.

Bb 
kase sartil sai
f a# a c1 a# a#

Bb (actually Ab cal also go here..but its Bb in OST)
mazya vina dis tujhe
f  g#   g   f   d#

Eb                Ab     Bb
sartana ani saang saltil na
d#   g   f  d# d  c  d#  d

Bb
gulabachi phula dona
a#0   c   d  d# d c

Bb (can also try Ab)
roj ratri dolyavara
c   d     d# f d# d

Bb
musu musu paani sang
d      d# f a#  a c1

Bb                   Ab     Bb
bhartil naa..........bhartil naa
a#  a#  g# g f d# d  c   d#   d


Stanza:

Bb                    Bb
Pavsachya dhara dhara mojatana disa sara
a#    d   c   a#   g# g#  a#  a# a#  g#
(remember the notes are elongated)

Bb                   Eb
rite rite mana tujhe ure
g#  a# g# g    f     f g

Bb                   Bb
otha bhara hase hase oratun vede pise
a#   d   c   a#   g# g#  a#  a# a#  g#

Bb                 Bb
khol khol kona aat zure
g#   a#   g#   g   f a#

Bb
aata jara aali mili
f    a#   b   g  f

Ab
tujhi majhi yatha nili
f     g#    g  f  d#

Eb                Ab      Bb
sosatana sukhavun hashila na
d# g f   d#  d    c  d#   d

gulabachi phula dona
roj ratri dolyavara
musu musu paani sang
bhartil naa..........bhartil naa