I'd say thats about right. I wouldn't go at it without a full staff of maintenance and operations. If you're having to pay out the maintenance bill to a 145 repair station, you're shooting yourself in the foot. Also try to get your own fuel farm and pay wholesale, or at least work a deal with the FBO from which you might/will be operating.
The real money is the consulting FOR the 135 companies. The people my boss contracted are paid close to, if not more than, what a top end lawyer makes per hour. It is a father/son team, the father being the former director of the South Carolina FSDO. They also got that large, well known 91K operator up and running when the FAA started requiring fractional companies to go through basically the same certification process as 135 operators. Their tail numbers end in QS if you need help figuring out the company.
DO NOT, I repeat, DO NOT, ever, ever, ever buy one of those pre-written 135 applications. You walk into the meeting with the FAA with one of those and you will be laughed out when you don't know what the heck is even in YOUR OWN APPLICATION. The FAA has told me that they have asked people to leave their offices and come back when they were better prepared. Its just like a commercial check ride...you better know your stuff cold. After all, you're ASKING them to allow you to carry paying passengers around in multi million dollar airplanes. It ain't no joke, and shouldn't be purchased over the internet.