In this when I say A maj 7 I mean A with the middle of the three fingered strings played on the first fret! 
A
When I buy my mansion
     A7M
I'll invite the world to stay 
      D 
So everyone can see
     A
A Picture of Dorian Gray

A
We'll sit by a river
A7M
drinking lemon tea
D
And there's a thousand idiot russians
A
in midget submarines

Chorus:
A
You can come and stay
A7M
You can bring your friends 
D
You can come and stay
F#m
For a day
                 A                                      A maj 7
And see a picture of dorian gray
                   A                                   A maj 7
And see a picture of dorian gray

A                                        A maj 7
Take you to my mansion,see my gallery
D
Lots of pretty pictures
A
All of them of me
A                                A 7 
We'll sit by the river drinking lemon tea
D                                                  A
Eat tiny cucumber sandwiches made by Emily

A
You can come and stay 
A maj 7
You can bring your friends 
D
You can come and stay
F#m
for a day 
                   A                                      A maj 7
And see a picture of Dorian Gray 

and the just repeat the song but on the second time play the last line a few more times