In my country, you cannot legally get a phone number not linked to the identity, and the prices are relatively high on the black market. Also, the phone discloses your location with pretty good precision, especially in US where everyone is living in their own house.
Phreeli [https://www.phreeli.com/] allows you to get a cell number with just a zip code. They use ZKP (Zero Knowledge Proofs) for payment tracking.