Congratulations on the offer! On your question: it just depends on how clear and firm YOU are in your communication. Just be open and upfront about why you need some time to make the decision, and give them a definite date for your decision. That's all you need to do.
Cheers, Sidi
 
							 
						 
                                            
                     
                     
                 
                 
                 
                     
                                        
    
    
                
     
                
                                     
                     
                
                                     
                     
                     
                
                                    