[CO] Rent room in primary residence - unclear on eviction laws

Location: Douglas County.

I have a tenant/roommate/lodger(?) who has been here about 7 months. They have been late on rent every single month and have not paid for March at all.

For this and other reasons I want them gone. One article on a law firm's website says a 10 day written notice is required, another specifies a 91 day notice, another says 30, etc.

I own the house. This person has signed a lease and is not month-to-month.

Can anyone clarify what steps I need to take?