On RetroMUD, you need to either save your items in a chest placed in a
castle 
(see help spell create chest and help castle) or save them in a rent room, 
which is  what you will probably use as a newbie. Rent rooms are located in

every major city (as seen on the map) and cost 500 gold per-day to use.
Inns 
exist in some cities and cost 7000 gold per week.  There is a crate inside 
each rent room which allows you to hold up to 6 pieces of equipment and a 
wardrobe inside inn rooms allowing 15 pieces of equipment. 

The commands in the normal rent rooms are as follows:

rent : This allows you to rent for X amount of days, and if you
already 
have a room rented there that has not expired, you can add the amount of
days 
left on the room by any amount at 500 per-day.

rent : This is the same command as for rent halls, but for inns. 
Inns
can only rent by the week.  

look [at] list: This allows you to see the list of people who are using
rent 
rooms at the current inn, as well as your own. This is useful for checking
how
much time you have left on the rent room. To make this even more useful,
use 
the 'set' command (see help set) to set your time zone, allowing you to 
determine exactly when your rent room will expire. 

enter room: allows you to enter your rent room

If, for some reason, your rent room expires, the items in your crate will
be 
claimed by the establishment, and thus lost to you.

Also, when you start getting equipment that's really worth saving and you
save 
up a lot of money, you should ask around if anyone has space in their
castle
for you to live, since it doesn't require daily/weekly payments, and most 
people have room for extras.