I've been running down the many rabbit holes of SharePoint Search options, and can't seem to determine what would be best for my problem.
We are using High Trust Sharepoint Apps to provide our users with custom functionality. Now we need to include the data generated by these apps in the Host Sharepoint search. The system is set-up with two primary teams that are not allowed to see the other's data, with a 3rd entity able to see both. The apps maintain this separation based on a user group they belong to - Team A seees Team A, Team B sees Team B, and Control sees both. The search results would need to maintain this security set-up. Additionally, there are attachments included in the app's data, and for bonus points would like to include that in the search as well.
I haven't found a similar solution (maybe it's so common it'll be a Duh! moment for me), and reading up on all the various SP 2013 search options hasn't given me a lightbulb moment yet. (A lot of, OMG that's going to be a very clunky way to do this - there must be a better answer!)
So, in a nutshell, what search method is best suited to handle this situation, and perhaps some pointers to good examples. Also, we're a very small shop of developers on a private network, so we don't have any SP admins - just us developers faking it.