If you’re a poor vampire, how do you legally get enough blood without harming people?

Imagine that you become a vampire. You need to drink blood every day to survive, but you don’t want to hurt humans. At the same time, you are too poor to buy blood with money. So what should you do?
Become a hospital cleaner
Every time the operation is performed, the patient will have some normal bleeding. Generally speaking, this blood will be treated as medical waste.
If you become a hospital cleaner, you can drink the blood. Legal and did not harm anyone.
However, it should be noted that the blood may not be fresh, and it will also contain various liquids used in the operation, as well as broken bones, disinfectant, etc. It is recommended that you strain them before drinking.
Do you have a better solution?
