> Meanwhile, large chunks of cities have relatively affordable, but not as attractive neighborhoods with homes that could be converted to house the homeless for a fraction of what it would cost to build new housing.
If they are "relatively affordable, but not as attractive" they are probably largely housing people currently, and not available to house the homeless.
If they are "in total blight, with abandoned neighborhoods, with windows blown out", they've probably also been stripped, structurally compromised, and contaminated with hazardous materials, and already sheltering squattors, and would need to be cleared, cleaned up, demolished, and have new housing built, making it a more expensive (excluding whatever differences there are in land costs) effort to use that space for housing than other places which might still require demolition and new construction, but not the clearing effort.
> Just the other day, I heard a news report in my area where they allocated money for homeless at $100,000 per bed in order to add more beds to an existing shelter in the downtown area. Yet this city has neighborhoods with cheap and unoccupied homes that could be bought to house these homeless for much less than 100,000 per bed.
I suspect if you research what the $100,000 covers, much of it is stuff that would still need to be done after buying the units. At least that's been the case most of the times I've seen comparisons like this.