I understand that it can be difficult to quantify the value of hosting a press trip.
On all press trips I undertake I sell numerous features to various outlets, across print and online media. The shelf life of the material gathered from a trip is generally 2–3 years and I always sell further features after my return from a trip.
See the following case studies for details of what I can offer you and your clients:
Macs: walking holidays
Jucy: car hire and campervan hire