The plan is for members of the group (and that means anyone interested and turns up) to go on field trips and look at what you can get for different prices, and how far people think the cost:number of target rent flats ratio can be stretched.
*Passivhaus is a German concept, where buildings attract and retain maximum sun / cooling from the natural environment, and are then insulated to a level where they need almost no heating
http://www.passivhaustrust.org.uk/what_is_passivhaus.php . In this development it is estimated hat Passivhaus would add £15k to the build cost of each home. Is this a priority? How would it be paid for? By fewer target rent homes? By charging more in rent (because the occupants would enjoy massive savings n energy bills) - this is exactly the sort of thing the group will be invited to advise on.