Ibis styles Delft
For budget options please have a look at hotels or hostels in Rotterdam. Accommodation in Rotterdam is significantly cheaper than in Delft. The (public transportation) connection between Rotterdam and Delft is excellent.
Hotels and hostels in Rotterdam: https://en.rotterdam.info/sleep-tight-in-rotterdam/
Ibis Budget at The Hague-Rotterdam Airport
Student Hotel Rotterdam
Book online or via your local travel agency.