Half that for mates rates, my tanks were smaller!
75g is 280 odd litres, mine were
120l all inc, good cond. new filter (vodka)
60l everything but a hood, exc cond. (free)
What's the asking?
£400-
£200, minus one day labor, trust me, you'll take a day moving fish water tank, then re setting it.
What's a fair day rate? 120+ ($180) that's fair, more is always good!
Anything less than 80 is fair. It is a sizable tank but it's used with stock.
What's new price? 600? At discount time maybe less.
80 and he helps, that's fair.
Even then you have a BIG fish to deal with, if it's small start saving!
280 litre (approx to 75 us
gal) used in the uk, 250 ish. Quick search but could possibly find cheaper.
(Exc. cond. all inc. no stock)
(Just checked, current rate is about $390)
So it's a fair price to somebody else.
Are you his mate?
Say advertise it, if it hasn't gone in three months. Cheers!

And he helps!