If you are the owner, you'll have to do it yourself (Trulia only pulls from Tax Records and unless you want your taxes to go up, you should only change it on here and hope the assessor doesn't see it).
1) You must be the owner or agent for the owner
2) Just click on the link you included
3) Under the address there is a link that says 'Edit Home Facts' which will bring up
a screen to log in to Trulia (if you are not already).
4) Follow instructions to change the home's facts.
Hope this helps.
Realtor since 1980
(651) 457-HOME (4663)