DemographicsGostwyck is approximately 83.87 square kilometres. In 2016 the population of Gostwyck was 27. The population is 50% male and 50% female. On average the monthly mortgage repayments in Gostwyck are $0 to $299. The most common weekly income bracket is $650 to $799 per week. Weekly rents in the area are on average $0 to $74.