费用 almost always refers to money 花费 can refer to time, work etc. 消耗 is kind of a term in production/manufacturing. 原材料的消耗。 人力、物力的消耗。

花费 means expenditure, can be money,time etc. 费用 means cost,charge, just refer to money. 消耗 means consume. it prefer material. 1. 花费 and 费用 can be interchangeable some place.

Usually the meaning 費用(=费用) in English is expenses, fees, charge. Like production costs, the cost of living, and so on. It’s about money. You can see 花費 as a verb. 花費 can be used when you want to say something take you time to do, or you spend time/money on something. Ex 1. It took me two hours to do something. 2. I spent 100 dollars on books yesterday. 消耗 usually means ‘consume’. Refer to consume energy, time, resources.