I'm not sure about other housing programs, but admin costs ranging at about 10% are not uncommon—I would say unfortunately—especially for programs that disburse millions of dollars to one recipient. It's not atypical to have admin costs of about 10% of total program costs.
For housing programs, it depends on the nature of each program. For example, programs that are capital transfers are a one-off, so there tends to be less administrative burden, if I'm correct, rather than ongoing transfer payments for which there seems to be a need for ongoing monitoring of expenditures.