As a loose reference, I do actually have a character part way through the story on an early post HW quest 'In the Eye of the Beholder' as a reference. She has done every dungeon, trial, alliance raid and normal raid..well, for the most part, still some stuff to clear up in HW, but she has never done any roulettes or ran any dungeon more than once. Never spent money on weapons (except to get the crafted weapon to make the ARR relic). This is pretty much as minimal as you can get just playing through the story and unlocking things. I also have not skimped out on using teleports.

Current Gil, 700K, I also have 219 Allagan silver, which is 109.5K gil and another 30K in Allagan gold. There is no chance the teleport fees are going to cripple me and this is before we even get to SB ahere you will get even more gil from quests.

It wouldn't surprise me if someone had a couple of million just doing the story through to the end of ShB.