Handling "not interested"

"Not interested" is usually a reflex rather than a decision, because it arrives before the homeowner knows what you are selling. Treat it as the door closing on the interruption, not on the offer. One short, specific sentence about why you are on this street restarts the conversation more often than any rebuttal does. A second attempt rarely helps.

It is not about your offer

The timing gives it away. If the words arrive before you have described anything, the person is declining the interruption rather than the product. That is a different objection and it responds to different things.

What actually restarts it

Specificity. A concrete reason you are on this street in particular gives them new information, and new information is the only thing that can reasonably change a reflex answer.

Rebuttals do not work here because there is no argument yet to rebut.

Once, then leave

One attempt is a clarification. Two is pressure, and the second one converts a soft no into a firm one and occasionally into a complaint. The cost of leaving is a single door.

Common questions

Should I push past "not interested"?
Once, with new information rather than a rebuttal. After that you are trading a door you already lost for goodwill on the street.
Why do people say it before hearing the offer?
Because they are declining the interruption. At that point they have no information about the offer to be uninterested in.
Is "not interested" the same as a no?
Log it as one and move on. Treating it as a callback fills your list with doors that never gave you a reason to return.