2 ways to double your money = June 2019.
That brings a 1*1*1800 item down to 450 gp, which is
within the range of Mercantile feat at level 1 starting.
The average commoner 1 in any particular town
still can't carry it = limited to the "treasure" 300 gp,
but they've got it stashed safely at home < 900 gp.
A small place, quite unassuming really.
How many 1st level spells are there (+ there) ?
You call that optimization? That's literally
canon in Eberron! Villages have have communal, unmovable, magic items that increase productivity like a prestidigitation powered laundry machine or a refrigerated storage space for crops/meat (which will then be transferred to Orien's portable fridges for transport). All you've done is create a guy who can rent it out.
Actually, speaking of renting, the Landlord feat from the same book. It provides free funds for stronghold building every level (which accumulate) and doubles the value of further money you put into it. Sadly it requires you be 9th level to take it.
edit: Yes I know Mercantile is from a FR book and tied to locations there. That actually makes it worse because if you actually do something useful with your magic item the Harpers are going to come murder your level 1 ass for making civilization progress beyond what Myth Drannor had (Why are they listed as a Good aligned organization again?).