I have four treadle machines and a cabinet machine. I didn't pay a whole lot for any of the Singers, and not too much for the Franklin.
1910 Singer 66 Red Eye Treadle, 5 drawer base = $50.00
1924 Singer 66 Red Eye Treadle, 7 drawer base = $35.00 + expenses to return it to a treadle. It had been electrified.
1910 Singer 9W-7 Treadle, 5 drawer base = $30.00 + expenses to repair treadle base
1911 Franklin 1911, Parlor Cabinet = $160.00 + expenses to repair cabinet
1948 Singer 66-16, Cabinet = $20.00
The machines are out there. And you don't need to pay outrageous prices either. Singer made many thousands of the Red Eye machines, so $900 dollars is way out of line.
JMHO
Joe