The base cost of a project is equal to the transfer cost that will be charged by Production to Marketing for each unit of the future product, assuming an initial production batch of 100,000 units. Note that the transfer cost will decrease if you produce more than 100,000 units, as explained in the Productivity Gains chapter.
You may ask the R&D department to develop the project at the lowest possible base cost also called minimum base cost. This cost depends on the project characteristics: the higher the level in each attribute (Processing Power, Display Size, etc.), the higher the minimum unit cost. There is one exception to this rule: unit cost will increase if you try to reduce the carbon footprint of your products. Developing a project at the minimum base cost will usually be quite expensive in term of the development budget. Indeed, the R&D team must not only develop the new characteristics requested, but also select materials and technologies that are compatible with the low cost target.
You may also ask the R&D department to develop the project at a specified base cost, higher than the minimum cost. This will give more flexibility to the R&D team in the materials and technology selection, and is likely to reduce the development budget. Obviously, the desired base cost must be compatible with the expected brand profitability, taking all factors into account: price, distributor margin, production costs, marketing and sales expenses, etc.