旅馆: provides living, food and drinks, amusement. This is focused on sleeping.
饭店: also has the meaning of 旅馆, but more functions, such as feast. This is focused on food and activities.
When you are going to use a work which means only, can use both "只" and "光" or "仅" or "单".
When you are going to describe possbility, "可能" or "也许", both ok.