think it was 25-30 solo fc's when i got my first sin to 150. didnt count the mats but yea it takes a good couple few to get 149-150 gl :3
I did solo FC on my sins (yes, more than one) and I kill all in there.
(Skip Dragoons, PWI crippled their XP to 45, to stop FC glitch leveling there.)
It was 5.4% for all mobs and boses (including Elementos on 2nd boss),
and 1.1% for mats. Plus about 22-24 mill coins per run, if you're not
"too proud" to pick them.
That way you need 16 runs. Each run 55-60 min.
Or 12 runs in FC for 24 Pure Gods, and 8-9 in PV, to mix a bit for refreshment.

Use Chill of the Deep for mobs (turn it off for bosses), and try how much you can
pull for Subsea and Earthen. Big room can pull half and half. Third corridor pull
directly to boss, the rest of corridor you will run anyway, no need to make circles.