A quarter of the population of the city is below the poverty line. If the intent is to offer them subsidized broadband, let's assume we get no capital recovery from those households. That brings the cost to $4,666 per household, or $9,300 per subscribing household.
This is high, but not out of the ballpark. Verizon spent about $3,500 on average for each paying subscriber for FiOS. Chattanooga's system was about $5,500 per household.