The question is not how many times you increase HP or cost, but how many more isk you can travel with and still be un-profitable.
with non-expensive fit I can get 600k ehp. That means that vs nades, if you consider 1B items requires 100k ehp to be un-profitable, I can hold 6B and will most likely not get ganked by canes
With expensive fit, I can reach 1M2 ehp (actually up to 1M3), that means I can have 12B isk in equip/cargo and most likely won’t get ganked by nades. considering the stuff costs less than 2B (invul and DC are the most expensive, reaching 300M each I think) it still gives a 10B cargo capacity.
for another ganking ship it is different.
eg check
https://zkillboard.com/related/30001384/201708182300/
the involved ganking ship is a catalyst, which costs 5.5M after looting the wreck and dishes 620 DPS * 26s = 16k hp damage before concord kills it.
so 100k ehp requires 6.2 of those ships to break , that is 34M is getting lost for attacker.
it then makes un profitable ganking a 68M-cargo.
of course with that setup, a 1B2 ehp orca with 2B drop is already profitable (it only costs 410M worth ships for attacker to kill it in .5 after concord fore spawn on a station). still it requires 75 catalysts on the grid.