Products are where WHMCS turns from software into a shop. A well-built product ladder sells itself and provisions itself; a rushed one generates support tickets about what the client actually bought. This is the order to do it in, with the settings that matter and the ones you can ignore.
Groups first
Configuration → System Settings → Products/Services → Create a New Group. A group is a page in the store: Web Hosting, Reseller Hosting, Managed VPS. Give each group a headline and a one-line description; the Nexus order form shows them at the top of the group page. Keep to a handful of groups. Clients choose faster from three tabs than from ten.
Create the product
Create a New Product, then the tabs in order.
Details. Name and description. The description supports HTML and is shown on the product card, so keep it to the three facts a buyer compares: storage, sites, traffic. Tick Require Domain for hosting products; without it Plesk cannot create the subscription. Set the welcome email to the hosting template.
Pricing. Choose the payment type: Recurring for hosting. Enable only the billing cycles you actually offer, usually monthly and annually, and price them. A common pattern is twelve months for the price of ten on annual, which is what "two months free" means. A setup fee field exists per cycle; most shared hosting is better sold without one.
Module Settings. Pick the Plesk module, the server group and the service plan, and set provisioning to automatically when the first payment is received. Full detail in connecting WHMCS to Plesk.
Custom Fields. Only if you need to ask something at order time that the module cannot infer, such as "which PHP version" or "migrate from which host". Every field you add is a field that can be filled in wrong.
Upgrades. Tick the products this one can be upgraded to. WHMCS prorates the difference and, with the Plesk module, changes the service plan in place. Clients who can upgrade themselves do not open tickets to ask.
Links. WHMCS gives you a direct order URL per product, for example:
https://billing.yourbrand.com/cart.php?a=add&pid=2Use these on your marketing site so a click on Buy lands on the right product with nothing to choose again.
Configurable options versus addons
Two different tools that are often confused.
Configurable options change the product itself: extra storage, more CPU on a VPS, a choice of datacentre. They are quantities or dropdowns priced per cycle, and the module can pass them to the server (a Plesk service plan add-on, for instance). Create them under Products/Services → Configurable Options, build a group of options, then assign the group to the product.
Product addons are separate items sold alongside: a WHMCS licence, a dedicated IP, a backup service. They have their own price, cycle and welcome email, and can be assigned to several products at once. Create them under Products/Services → Product Addons.
A rule of thumb: if it changes the server account, it is a configurable option; if it is a second thing on the invoice, it is an addon.
Free domain with annual hosting
Under the product's Details tab, Free Domain lets you include a domain registration when the client picks certain billing cycles and certain TLDs. Set it to annual only and limit the TLDs to the cheap ones; a free .io on a monthly plan is a loss.
Hide products you are not selling yet
Each product has a Hidden tick box. Hidden products can still be ordered by direct link and still provision, which is ideal for a plan you offer only through sales calls, or an old plan existing clients keep but new clients cannot pick.
Check the order form
Open the store as a client would: https://billing.yourbrand.com/store/web-hosting. Product cards, prices, the configure page and the checkout should read the way your marketing site promised. If the product description on the card is longer than three lines, cut it; the detail belongs on your site, not in the cart.
Change prices later, carefully
Editing a product's price changes it for new orders only. Existing services keep the price they were sold at, stored on the service itself. To move existing clients, WHMCS has a bulk pricing update tool under Utilities, which can update all services on a product at once. Announce the change first; the invoices will show it.
On VPSPioneer reseller plans the WHMCS Starter licence is included with Partner Grow and Pro, and the setup above is yours to do. This series walks through each step in the order that works.