The cost can often be tens of thousands. Some of the cheapest training is min. 10 000$ per dog, but in some countries it could even go above 50 000$. You also have to have a very specific type of dog, so usually the puppies picked for training are bred specifically to be service dogs. I don't know what the cost would be in Japan as I'm Finnish. I would guess the costs here to be around 10 000 - 20 000€. Luckily the blind person normally wouldn't have to pay that amount, but in some countries the blind person has to pay the training fees themselves. It's incredibly important to donate for this cause, as most training facilities essentially function through donations. Even internationally service dog training centers are massively underfunded and ignored. It is also very import to support service dog rights! Too many dogs and users are assaulted each year and discriminated against (like denying access to a business for example, which is illegal). For many people, their service dogs keep them alive day after day. Too often the work of these animals is ignored and belittled we should work toward a future, where no service animals are assaulted!