Linking a CPT to other CPTs in Tabs

I am in the process of building a directory for Racing which will have various CPTs – One for example for Racing Trainers and another for Stud Farms etc.

I would like to have other CPTs — for example for “Horses for Sale” and “Syndicates” and be able to link these to the Trainer — much as “Events” can be linked to “Places” — and show in a tab.

So while all “Horses for Sale” would show in the Horses for Sale directory – “Horses for Sale” by a particular trainer could also be referenced through the Trainers entry in the Trainer Directory.

Is there an easy way to do this or do I need custom development?

TIA
Conrad.