Once accepted, new members had to pay a membership fee in order to become shareholders and after so doing were issued a packet of shares that gave them an equal share in the Company. The fee was initially set at $3,000 and remained so for many years. Eventually it was raised in an attempt to match inflation so that later monetary contributions would roughly equate to earlier ones.
However, under Rainbow's original agreements, shares were not seen as an investment and members who left or died were meant to gift them back to the Community. For the first thirty-five years, new members could pay off their memberships in moderate installments - because the building of houses also required money. Such payments were negotiable and were designed to be affordable. No shares were issued until the fee was paid in full.
The number of resident shareholder members has stayed between eight and twelve since the early 1980s. In 2011 there are nine such, plus ten non-shareholder adult residents. Seven of the nine resident members have lived at Rainbow more than twenty years, five of them since the 1970s. All but two are NZ born and the two Australians have both been New Zealanders all of their adult lives.
Rainbow's resident members are settled, committed and know a lot about sustaining a Community. For many years they shared the parenting of children - to some degree - like an extended family.
Minutes of meetings were recorded in successive minute books and major agreements reached thereby were seen as enduring - since in theory every member was on board with them. Not until 1990 were these agreements combined into a single document. The only really formal meetings were the AGMs required by the Companies Act.
A process for new membership evolved, a process taking a minimum of fifteen months during which a lot of communication and cooperation would supposedly ensure full understandings were reached. This made joining Rainbow somewhat arduous. It would probably be unrealistic in today's climate.