Yes, you may choose to stay at whatever hotel works best for you. There are also great AirBnb options available (just make sure to look at ratings and reviews). **Please make sure you are booking in advance as February is during Cartagena's peak season.**
More info to come.
No, you do not need a visa to travel to Colombia, but please make sure your passport does not expire within 3 months of your travel.
More info to come.
While tipping is not mandatory, it's generally expected to show appreciation for good service. A standard tip is around 10% of the bill, but you can increase for exceptional service.
Yes, it's safe to drink the tap water in Cartagena and in most other urban areas of Colombia (like Bogota or Medellin).