We're looking for cart abandonment solutions, aside from general conversion optimization we can do ourselves. UpSellIt contacts us all the time, but we would like to have some options. There really doesn't seem to be a whole lot of options out there when conducting a search.
Would love people's recommendations!
Side note: We use a custom in-house CMS, so basic plugins/extensions for wordpress, magento, etc. won't help unless using an API is an option.