The site MusicTeachersHelper.com has a set of functions you have to pay to access. The features, like booking, billing, and letting customers log in to pay bills and see their schedule, are very nice, and have been very helpful to our business. However, their site is ugly. I want full control over the look of the site. I can modify the login page, but the logged in pages are php files I can’t access. I was just wondering if there is a more customizable plugin or other free or paid site out there that has most of these functions that will give me more control over the look of it?