Intro (Bruno Mars):
A5                        C#5
I wanna be a billionaire so fucking bad
F#5                           E5
Buy all of the things I never had
A5                          C#5
I wanna be on the cover of Forbes magazine
F#5                           E5
Smiling next to Oprah and the Queen
    F#5          E5            A5
Oh, every time I close my eyes
  F#5            E5             A5
I see my name in shining lights
F#5         E5          A5
A different city every night
C#5  F#5  B5
Oh   I-I  swear,
                    C#5
The world better prepare
                         A5
For when I'm a billionaire

Verse 1 and 2 follow the same progression as the beginning A5 - C#5 - F#5 - E5

3rd chorus is normal, but the 2nd chorus starts at "Oh every time I close my eyes..." 
has a little extra at the end of it where it just repeats billionaire. That little part is 
A5 - E5

The end is just A5 - C#5

If you listen to the song, you'll get the idea of the strumming. Its reggae-esque and a 
catchy song. Hope this helps everyone!