Finding the right external experts has a material impact on a project, and can include additional challenges when working remotely, across boarders and through different cultural lenses. For example, what could be interpreted as a final agreement in one culture, maybe considered a stage on the path of negotiation in another culture.
Aligning incentives with outcomes (and to avoid conflicts of interest) is difficult in any arrangement, however presents unique challenges internationally. Similar techniques can be used to those employed bringing together the buyer, target and specialist accountants (or legal, etc). It is important to understand the level of materiality to be deployed and the areas of concern being undertaken, in order to direct the advisors in various fields and get the results required.
In addition to references, it is always good, and even more so when working across unfamiliar cultures and regulations, to get multiple opinions initially to form the basis of where to source sound expertise and the required levels of performance.