A stone's throw from the palace where President Hamid Karzai has spent 13 years, a newly renovated home awaits him and his family. Karzai is due to step down after Saturday's presidential election. Under the constitution he cannot stand again, so the vote is setting the stage for Afghanistan's first ever peaceful, democratic transfer of power.

Simply by leaving his job voluntarily, something no other leader of the country has done, Karzai will be creating an important legacy for himself, diplomats and senior Afghan officials say. "The more important part of Karzai's legacy will be the successful achievement of a political transfer of authority to a new president," said the US ambassador to Afghanistan, James Cunningham, adding that it will be both an achievement and indicator of the country's future.

But Karzai's new home is a reminder that after 13 years at the helm, his influence is unlikely to end when he leaves office. The 56-year-old insists that after he hands over the reins, he wants a break. He has had barely a day away from his job since he came to power, and little time to spend with his wife and three young children. "If God gives me a life to go around, visit the country and enjoy myself and go to cafes, visit London during Christmas, and see the lights, visit places, work on Afghan education and be with the Afghan people," he said recently.

But few people expect a man who has so skilfully juggled competing factions, and outmanoeuvred his foreign financial and military backers, to slip into a simple retirement with his family.

Karzai will be relatively young for a former leader, and admits he would like a political role if his successor permits it. His new home would allow him to reach the seat of power in minutes; its garden backs on to the palace grounds.

"The president will be a happy citizen of the country, and if asked by the next president to advise him on issues, he will be happy to advise," said spokesman Aimal Faizi, who added that Karzai had turned down tempting job offers overseas. "He will be in the country and in the service of the people."

The three frontrunners for the top job, all of whom served as ministers under Karzai, have at least civil relationships with him and are unlikely to exile him completely. While his lingering power may be a threat, he could also be extremely useful to the new ruler as a powerful orator and master of alliances adept at balancing the country's ethnic and regional needs.

Karzai is believed to favour Zalmai Rassoul, a former foreign minister who emerged from relative obscurity to run for the top office and has the backing of Karzai's brothers Qayum and Mahmoud. Rassoul denies Karzai would be the power behind the throne, but said if he won, he would try to tempt his predecessor back into public life. "He will play a role, he's a young man who has played a key role in Afghan history and still has a lot of support," Rassoul said in an interview on his campaign plane. "It depends on him, and when I talk to him about it he says he wants some rest."