Miva Merchant - Shopping cart software with module-based architecture and very flexible storefront design functionality. Shopping cart engine provides open API which allows built-in modules creation by third-party persons and companies.

As for the developers themselves, unfortunately, they do not seem to offer authorized customization services. Flat-rate support system is quite expensive and only covers general questions and problems (plus some fixed range of shopping cart software services). Most of services and plug-in modules are much more expensive in comparison with ViArt which is 97% open sourced and allows any modifications by you or professional specialists.

Features

Miva Merchant

ViArt Enterprise

License fee

  995.00 USD

  299.00 USD

Multi-site

No

Yes

Trial period

No

Free version with restriction

Technical support

Flat-rate yearly licenses ranging approximately from $400 to $1000 and including various service packages, forums, knowledgebase.

Authorized technical support service, forums, FAQ, online manual, free unlimited support

Installation service

Installation service 149.00 USD

Installation service 50.00 USD. Free installation service for paid hosted clients.

Design & development
services

Not available

Comes with  20 pre-define templates plus 97% of source code, Custom development service and web design service

Store Operation Features

Support for downloadable
egoods

Not available

Yes

Affiliate system

Build-in affiliate tracking system

Yes

Real time shipping rates calculation

UPS - USPS - FedEx

Fedex, UPS, USPS V3, Customizable shipping modules and methods

Moderated product reviews
and ratings

Not available

Yes

 Statistics tools

Statistics for revenue, number of orders, top selling products, pages popularity based on log file analysis

General statistics and shop summary, Shop statistics, Top Paths Through Site, Top Pages Views, Shopping Cart Conversion Funnel, Visitors environment statistics, Search statistics. customized reports available.

 Taxes

Canadian & German VAT

Ability to set tax by state, country, product type, advanced tax structures including VAT.

 Orders management

Order status system, automated order notifications, automated and manual credit card processing, order search and filtering, possibility to export/import all and filtered orders, support of recurring orders, PDF invoices and packing slips

 Inventory tracking

Reports for number of orders, number of products,  options, product /category views sorted by date period, bestsellers, Out of stock messages, number of products/options in stock for every item.

 Security

HTTPS/SSL support, sensitive data encryption

Full HTTPS/SSL support
Encrypted customer data (Blowfish encryption)
PGP-encrypted e-mail notifications
Customer/admin access restriction by IP

For complete details

Catalog & Storefront

Number of products in
catalogue

Unlimited

Unlimited

Storefront customization

100% template-based storefront
100% CSS-based
Customizable menus
Customizable logo and
templates layout from browser
Built-in text editor

Multi-language support

Not available

Store interface, messages
completely multi-lingual

Extended product
specifications

Product options and variants

Extra custom fields, product options and components, dependant options, filters for products.

Marketing & Promotion

SEO Tools

Catalog, title and meta tags definition, URLs, site map generator

Marketing and promotion
tools

Upselling products, Discounts

Merchant Module, Rewards and Bonus Points Functionalities, Call Centre modules, 

Added Features

 HelpDesk Modular

No built-in components

Included

 Forum Modular

No built-in components

Included

 Classified Ads

No built-in components

Included