What can I do for not to delete the house accidentally when trying to delete an object for example?

[hallebarde]

...as I had to rez it again once because of that.

Tks

[Lindal Kidd]

Right click the house.  Select Edit.  Check the Locked button.

When an object is Locked, you will get a caution notice if you try to delete it.

[Rolig Loon]

Duplicate post.  Originally asked and answered in https://community.secondlife.com/t5/Land/Can-I-save-the-house-I-ll-modify-and-decorate-in-my-inventory/qaq-p/2971657/comment-id/12943

Please do not start more than one thread with the same question.  Doing that makes it hard for us to see what other people have already suggested, and it pushes other residents' questions off the page. In this case, you were probably right to have asked here, as a new question, rather than adding to your previous one. In general, though, it will be easier to get consistent, helpful advice if you only ask once.