I believe you might get two to be Harmless (in the event you want to paint the insides etc) But a single is probably all you’ll will need…normally far better to obtain an extra although! :) Thanks Pam :) I applied the Varathane sealer pictured higher than from the article https://kitchencabinetpaintingser56543.blogitright.com/4090324/a-simple-key-for-painting-bathroom-cabinets-color-ideas-unveiled