"In real life" is a prepositional phrase modifying the verb have.
Typically, you will want such modifiers to be placed as close as possible to the word they modify.
(Edited) Sentence 1 is standard English, and would work just as well as #4.
Sentence 2 works.
Sentence 3 produces great dissonance, as the phrase is placed very far from the word it modifies, and should be avoided.
Sentence 4 is by far the best choice, as it follows a standard layout for the placement of the modifier. It thus comforts your reader into a pattern he can recognize, whereas atypical constructions such as sentence 1 and 3 risk to create confusion.