Setup whatever bike you intended to train on as the position that works best for you. Setup so you can do multiple days of whatever distance you intend to ride. Any particular reason you are not bringing a bike that you use at home ?. If not shipping a bike (which is what most people do) I would measure mid crank to top of seat. middle of seat to middle of stem, height of h-bar off ground, etc.... and replicate those measurements on whatever bike you are renting or send that data to whomever is renting the bike so they can set it up. Bring the pedals, shoes and saddle from the training bike.