Do you have a written lease with the landlord or verbal only? If a written lease, are there any lease provisions that would cover this factual situation? When you requested the landlord to screen your apartment was there a discussion or agreement as to who would bear the costs? Did the pest control team inspect or treat any other apartments or common areas in conjunction with your treatment? Do you even know whether the treatment was effective, or will it have to be repeated?
In order to properly answer your question much more information and documentation will need to be reviewed.
Please review the terms of your lease agreement which should address pest control issues. For more information on bed bugs, you should google "bed bugs lawyer". I did it for you and found www.Bed-Bugs-Lawyer.com
Look at the lease but if this isn't addressed and the complex had an outbreak, then how could you be responsible for the fees? It sounds like a communal problem that the landlord should address.
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