When the wife read's the information on the painting, it says the captain lived from 1860-1902. But the painting is of a man much older than 42.
Andy bumps his head on the way out the window.
The couple climb through a window to look at the house to see if they want to rent it. When they leave the house, they climb back out the window, instead of using the door, which would not have been unusual to anyone passing by.