Hi, sorry for the late reply.
1) Is there a way to create filter dropdowns that handles a range of values. Example is the value may be 100 on an article, but we want a filter dropdown that says 50-150, 151-250, etc. I know a workaround would be to have two fields one for filtering and one for article view page.
-> I'm not clear about the filter you described yet. Could you provide me with more details or a screenshot explaining it?
2) Is there any type of webservices/API available for portfolio plus that would aid in syncing data from an external source. I've checked into joomlas API but it doesn't seem to extend to components.
-> What external source do you want to sync data with TZ Portfolio+? Joomla, K2 or Easyblog?
If it's Joomla, we do have Joomla migration addon that allows you to migrate Joomla articles to portfolio articles.