Sometimes changing the order of an adjetive can change the way they modify the noun and/or become more expressive.
With
llegaron a una posada, o hotel pequeño.
the speaker explains that the hotel was small. With
llegaron a una posada, o pequeño hotel.
the speaker emphasizes the the hotel was small.
In Spanish we have a special type of adjectives called epítetos. These are adjetives that highlight an obvious characteristic of the noun (thus, being completely unnecessary). Some examples would be:
- the white snow / La blanca nieve
- the cold ice / El frío hielo
- La roja sangre, el cálido sol, etc.
As you can guess it is used for poetic value, since we already know that the snow is white, the ice cold, the blood red, etc. Also, the epíteto doesn't need to go in front of the name, but usually it does, since this grants a more poetic value.
In you example, pequeño is not an epíteto (since a hotel could be big or small), but the use of a pre-nominal adjetive serves the same function as the epíteto, not your pointing or declaring a quality of the noun, but stressing or emphasizing that quality.
Other exmaples of this would be:
El hotel pequeño / El pequeño hotel
Su coche rápido/ Su rápido coche
Sus ojos azules / Sus azules ojos