The best way to reduce the cost of everything is to clear the Washington DC federal government of at least half its workers.
Talking to older people here in DC who are long-time residents, they tell me the growth of the area has been huge since they were kids. Up until fairly recently, the suburbs around DC were farming and horse communities. DC, at its height, had about 800,000 residents. We're down to about 550,000 now, but the DC metro area is about 4.5 million. A huge part of that growth has been driven by the growing size of the Federal government. Before WWII, DC was kind of a backwater Southern town for most of the year.