One of the Shabbos laws that seems to present a problem for a traveler who is a guest in a hotel is the following:  The Shulchan Aruch Orach Chaim 366, 1 writes that if there is a common courtyard surrounded by separate dwellings, even if this area has proper fencing or mechitzos, it is forbidden to carry any item from the yard to a house or vice versa.  Carrying in the yard itself if permissible.  In order to carry into a house the dwellers must make an eruv, i.e. collect flour etc. from the dwellers and have it baked on behalf of all, then this is considered as a communal domain allowing one to then carry from the yard to the respective house and vice versa.  

Could this apply in an apartment house or condominium where the common area is the corridor or lobby?  What about a guest in a hotel?  May he carry from the corridor to his room or vice versa?

Rav Moshe Feinstein, (Igros Moshe Orach Chaim I, 141) rules as follows in regard to any dwelling such as an apartment house or a hotel.  If it is a rental or leasing arrangement where the lessor (or landlord) owns certain appliances in the lessee’s (or renter’s) domain,  then the above requirement of an eruv does not apply.  He bases this decision on the many Talmudic and rabbinic sources that ruled that “tfisas yad” ownership of certain articles, appliances etc. are to be considered as all part of the lessor's  domain. This is true even though the renter has rented the apartment as his own private area.  Consequently this would be relevant to the hotel guest who has rented a room or suite, due to the fact that the hotel management owns many items in the rooms. 

Others who concurred with this principle were Rav Yaacov Orenstein, O.B.M. (Yeshuos Yaacov) in the 19th cent. and Rav Yaacov Breisch, O.B.M., (Chelkas Yaacov I, 207) in the past century. Although they arrived at their ruling in a different manner, nevertheless, they agreed on the outcome of not requiring an eruv in the above circumstances.