Sorry, no GPX compilation here, but I can confirm that we never had any problem at bringing a tandem into a hotel room, both in Formule 1 and Ibis Budget hotel. Either the staff don't care, or there is no staff at all.
If you are of the sort of people who can sleep anywhere, Formule 1 hotels are a great value. Otherwise, if you need a more comfortable bed, Ibis Budget is a better option! Also look for Premiere Classe and Campanile hotels, the equivalent of Formule 1 and IbisBudget in a competing group.
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