Interior desing = planning, makeover and furnishing the property for customizing it to the requirements and style of the owner(s). The owner sets the budget.
Home staging = furnishing/refurnishing the property (which is frequently inhabited) for fitting it to the taste and requirements of the more customers-to-be. The staging contains smaller makeovers but the spent amount on it should be maximum the 5% of the property’s value.
Real estate development/investment = buying a property in bad condition, then reselling it after a full makeover. It should be done in a way that the property fits the taste and requirements of the more customers-to-be. The spent amount and the profit after selling have to be conciliated.