As the Rio Summer Olympics come to a close, the attention has turned to preparation for Tokyo 2020. Organisers in Rio have had to contend with a range of problems including safety, plumbing and the budget. Money and budget: Host cities tend to go over their proposed budgets and Rio has been no different. The initial budget of around $3bn (£2.3bn) is – according to a University of Oxford study – now thought to be overshot by more than 50% to about $4.6bn. And towards the very end, the fate of the Paralympics that traditionally follow the Olympics, was suddenly in limbo because of a lack of funds. They have now been cleared to go ahead but only after major cuts to the budget. So the lesson from Rio would have been to watch your budget and stick to it. But it seems that Japan has somewhat missed that boat already. Granted, this is only an estimate so far, but the numbers are staggering – Tokyo’s budget is already thought to be six times the original proposal, and we are still four years away from kick off. The most expensive Summer Games so far were the ones in London in 2012, with a final bill of $15bn. The Winter Games in Sochi though topped even that, costing Russia around $22bn. Planning and organisation: The 2016 Games included quite a few organisational hiccups with some athletes, for instance, complaining about the Olympic village not being ready. There was also that pool that turned a swampy green colour. It seems like those particular points should be lessons fairly easy to take in. If sticking to the budget doesn’t work, at least make sure you stick to the schedules. It makes a pretty poor impression when malfunctioning plumbing rather than medals make the headlines in the first days of the games. Many of the organisation details can only be judged once the Games are under way, but Tokyo has already seen a spate of problems. It was forced to scrap its design for the 2020 official logo shortly after it was revealed, over allegations of plagiarism. A theatre in Liege, Belgium has a strikingly similar logo it had been using for years and the original designer filed a lawsuit. Out went the first Tokyo 2020 logo, in came a new one. But there have been more problems than just the logo. The Olympic stadium was initially to be built by renowned British-Iraqi architect Zaha Hadid who had drawn up a futuristic original design reminiscent of a spaceship. Yet the ambitious project would have cost 252bn yen ($2.5bn, £1.9bn) making it the most expensive sports venue in the world. After much controversy, the plans were axed, the country’s education and sports minister stepped down and a new design by Japanese architect Kengo Kuma was picked. At 149bn yen, it’s far cheaper, although that too is an initial budget only. Crime and safety: Crime and security were of major concern in Brazil. The country has the world’s highest murder rate, though Rio itself is not among the worst cities. But robberies, mugging and the personal safety of fans and athletes had been a big worry ahead of the game. The US Overseas Security Advisory Council (OSAC) had a damning verdict for Rio, giving it a crime rating of “critical”. What exactly does that mean? “In Rio, robbery, assault, burglary and theft are concerns for foreigners and Brazilians alike. Criminals are determined and sophisticated, which requires visitors to be alert to their surroundings. Violent crimes (murder, kidnapping, carjacking, armed assault, and burglary) occur regularly.” In addition to crime, there was also concern over the Zika virus in Brazil, although the organisers and the World Health Organization did their best to try to allay the fears of fans and competitors. For Tokyo, the same OSAC rating is “low”, specifying that “violent crime is rare but does exist”. But security is always a top concern for events involving huge numbers of people, and that will be on the minds of Tokyo’s organisers.