>>72016575my rough breakdown:
$1.5k flight
$50/day hotel. this was an real (apa) hotel at a convenient station too, not a capsule. you can do much lower
<$30/day for food. lots of combini and chain restaurants. gyudon at yoshinoya is fucking amazing and costs like $5 usd. yakiniku for like $20.
$10-15/day for transportation
a few hundred for expo/stage tickets, penlight, tshirt, towels
once you're there, it's incredibly cheap