I've run multiple TOC's since the 1990's, including the first one used by the Corps of Engineers. The original was a FFP PI (firm fixed price plus incentive), which the customers and contractors both liked very much. At the time, title of TOC was selected to eliminate having any case law history, to preclude constraints placed by FARS such as non-prepriced items, and to streamline the process. Not having worked in contracting for over 10 years, not sure how other agencies do the work now. The incentive clause was removed after I left the business.
JOC's had a long contract history, JOC books took time and money to prepare, and required frequent modifications for items that might be in Means, but not the unit price book.
RS Means served as a cost and price basis and the AIA or UFGS served as basis for quality.
I'm working with the contracting and engineering office where I am now to see if TOC would be best fit, and whether incentive would be allowed. Haven't checked on contract history for appeals/claims so I have another step yet.
A problem, and a benefit, of the TOC is that you must have trustworthy people in the field, or have a dependable verification of scope and price separate from the construction manager. I used to do up to $10,000,000/month in TOC.
For limited scope and repeat business, you may want to look at Requirements contract and BPA's as well as TOC.
The best way to start is by having a good contract acquisition plan. Knowing what projects you would like to do, when and where is a good negotitation item when you can start by saying "We would like to do X amount of business of this specific nature. Would you be interested in bidding a unit price cofactor (and incentive fee) for this amount of work we foresee coming?"