you want an antminer l3+

you can set it to do 600 watts 24/7/365

so 24 x .6 = 15 kwatts a day

or 450 kwatts a month.

it will earn 1 dollar a day or 30 a month

point to nicehash it will send you btc.

it is fairly quiet and suits your needs close to perfectly.

You can get it for about 200 with a quiet psu shipped to hawaii.

note you possibly could get an antminer s15 and run it on low speed

but it will pull 900 watts and about 700 kwatts a month

it will earn about 2 dollars a day. you must use  240 volts.  i think it costs about 400.

if you want more info about these older units shoot me a pm.

note the antminer L3+ uses 120 volts it is okay

the s15 use 240 volts it may be better.