“The V-1 was history’s first mass-produced cruise missile. Each could carry a 1-ton warhead nearly 250 km (160 miles) at a cruising speed of 650 km/h (400 mph).
“Each V-1 cost about 5,000 Reichsmarks or $2,000 in 1944 (that’s the equivalent of about $27,000 today).The 21-foot-long flying bombs were made mostly from sheet metal and plywood. Each took about 350 labour-hours to produce. Concentration camp inmates and slave labourers toiling at the Gerhard Fieseler Werke plant in Kassel did most of the assembly work.”
“eventually radar-controlled batteries and proximity-fuse shells became available. By the end of the summer, three-quarters of V-1s launched against Britain were being brought down by flak.”
https://militaryhistorynow.com/2015/02/06/buzz-kill-15-amazing-facts-about-the-v-1-flying-bomb/