We also stayed at Premier Inn Edinburgh City Center Royal Mile. We did pay the 9.5€ per person for the fully cooked breakfast buffet. A continental breakfast was less. We felt the breakfast was well worth the cost.
As already stated, it is a block off the Royal Mile and close to Waverley train station, the castle, and Holyrood House. We picked up the bus to visit HMY Britannia from nearby Canongate Kirk. For Outlander fans, across the street from Canongate Kirk is the Museum of Edinburgh. It was used as the interior for Jamie’s print shop in the series. The print shop entrance for the series is behind the museum on Bakehouse Close. For Harry Potter fans, I recently read that the Elephant House pub reopened after a devastating fire.