@timconsidine Thanks for your question. There's one package called SeoToaster Ultimate that installs CMS/CART/CRM in one shot - you can then decide what component to use or not to use as your needs evolve.
I know it can be a bit confusing. In addition to the web presence/sales automation front-end SeoToaster Ultimate, there's a cloud marketing hub component that we call the SeoSamba Marketing Operating System - MOS.
MOS combines analytics, social marketing , review, citation management, call tracking, SEO reporting, and more to any digital asset type, it can only execute on-site SEO tasks (Meta alignment, content writing, URL optimization with automated 301, deep-linking, interaction with Google console...) from a central location, as well AI-driven blogging to SeoToaster Ultimate and WordPress sites.
You can find out more about it here; https://www.seosamba.com/white-label-marketing-automation-software.html - our entire stack can be white-labeled by solution providerrs. We have a few baked-in business models too for fellow professionals like subscription, pay-per-lead, pay-per-SEO, affiliate program...
Now, back to the front-end host, you can decide to build your entire front-end stack or just decide to use SeoToaster Ultimate as a... CRM and link it up to the rest of your stack.
In that case, you would probably use the web forms builder to get leads from other sites https://help.seosamba.com/form-builder.html - but you could for instance rely on SeoSamba's telephony services to provision a phone number anywhere in the world for $5 and then get see inbound calls placed through that line create leads automatically in 1 click in your CRM - https://help.seosamba.com/cloud-tracking-services-in-crm.html - you can also download our soft console to place calls.
- we also have a very neat built-in parser for inbound email to lead creation, zapier connector, rest API, and of course we support IMAP to keep inbound email in sync - more info about the CRM here: https://www.seotoaster.com/crm/
@humptydumpty product variations are built-in - no plug-in needed either. https://help.seosamba.com/managing-product-options-with-website-builder-ecommerce.html - You can store them in a library and apply them across products, you can also edit them using a csv import. You can mass edit products from the CRM area under mass product tool - https://help.seosamba.com/product-mass-action-in-crm.html
We have a few specialized editions too, one has to do with real estate with IDX integrated. Another is in the memorial business ERP, another one is for restaurants with a kitchen orders intake/delivery, one is for franchise businesses and we have more coming..
Besides the mature and very capable mobile CRM and Social native Apps, we have already an alpha version of our upcoming IOS/Android POS app, linking SeoToaster Ultimate web stores including catalogue/transactions/customers and options to a retail environment. The POS app features built-in barcode reader, it support contactless payments, cash, cc scanner, and attached card readers/receipt printer - ship to customer, or pick up from multiple store.
Sorry I feel like I'm monologuing again.. we're quite enthusiastic developers...and I love what the team built 
Always happy to provide answers, including terse ones, no seriously try me...I'm sure I can do it..