Check out total cost of elections here https://www.opensecrets.org/bigpicture/index.php?cycle=2012

Office Space and Staffing Allowances GSA is authorized to provide “suitable office space, appropriately furnished and equipped” at any location within the United States selected by a former President.32 The funding for this provision becomes effective six months after the expiration of a President’s term of office. The FPA does not provide specifications or limitations pertaining to the size or location of a former President’s office space. Since a former President’s pension is comparable to the salary of the head of an executive branch agency, GSA has historically applied “the cabinet-level office standard” for the quality of a former President’s office space, equipment, and supplies.33 Office space costs for the living former Presidents are shown in Table 3.
 Table 3.
Annual Office Space Costs for Former Presidents,
FY2014 Former President Location Square Feet Cost
Jimmy Carter                        Atlanta, GA 7,070 $109,439
George H.W. Bush               Houston, TX 5,379 $179,691
William J. Clinton                New York, NY 8,300 $414,380
George W. Bush                      Dallas, TX 8,237 $420,506 

Is all this necessary?  this is just rentals.  With today's technology they could just stay home and be president using mobile devices instead of wasting money like this.  

I know too logical right?