I suggest using google maps. Do you have existing database of hotels, what's its format? It is also possible to allow user to save the map and later after they start their travel they can upload photos, videos, notes, etc. and attach this to the map. Users can make private notes or share with other users. No requirement for flash - it will make easier to use on mobile devices. Please contact in PMB to discuss details and estimate price and delivery time.
Best Regards,
Zeke