You must first know how many jobs your company will give him. If you don't have this common sense, how can you negotiate the price with him? !
If you are busy every day ~ the size of the fault continues, then pay for the monthly service! It's a good deal for you!
If you are not busy every day, you can pay by the hour.
I come from Suzhou. In Suzhou, the monthly subscription is generally in 500 yuan, and the hour is one hour in 20 yuan.
Don't worry, you can't do it. After all, it maintenance is not complicated. There are many such people! !