The International One Metre was intended to be a restricted and inexpensive high-performance class for radio-controlled yachts, capable of being built at home. The result is certainly quick.
The hull is governed by a simple ‘box’ rule, with limits on the overall draft, hull draft, weight and sail plans. They have three rigs for different wind ranges.
You should be able to buy a good second- hand club-level boat for around $1500, while a boat which is competitive at regional level will probably be upwards of $2000.
You can download the class rules here, and here an interesting article on the the evolution of the design.
Tuning is both critical and sensitive to small changes. Ask other members for advice or look on the web.