HDP, its Spec Cost Update add-on tool, and HDP Online Bidding can be purchased two different ways:

Purchase Online:
The easiest method is to purchase online using a credit card via Verisign's secure payment processing site. By using Verisign, we never have access to your credit card information.

I want to purchase Housing Developer Pro.
I want to purchase the Spec Cost Update add-on.
I want to purchase HDP Online Bidding.

Purchase Order:
For organizations with appropriate credit history, software can be purchased via a formal purchase order. Payment may be remitted via check drawn on any bank with operations in the USA, or payment may be wired directly to our bank. Call or email for details.

HDP Upgrade:
To upgrade to HDP 3.0, your organization will need to be a registered user of either HDP 1.0 or HDP 2.0, and we will need to confirm your previous purchase and send you an email upgrade quotation that will include a link to purchase using a credit card.

Or if you prefer, you can use the quotation email to generate a purchase order or payment by check or money order. Go to the Upgrade HDP Request page to initiate your upgrade request.