If you're thinking about nightclubs, cars, and diamonds
Then it may be insignificant to you
It's not a life of a rich man
Or: It's not a rich life
But it's a good time
And if in the house we can't afford air conditioning
This line means he can not provide enough so as to have air conditioning in the house. The expression 'no alcanza' is sometimes used to say 'there isn't enough money for something'. 'El aire' is a reference to 'aire acondicionado'.