We've a beautiful 8 year old female domestic short-hair cat. Have had her since she was 8 weeks old.
Quite shy, skittish temperament. Easily scared by other neighbourhood cats. Likes lying around house cosy, not fan of being stroked much.
Is not an indoor cat, goes outside at night most of time.
Has not used a litter box since she was kitten, as my personal preference was for her to pee/poo outside as we have children and I feared them touching litterbox.
But, we're getting ready to move house. Moving next month.
I've no idea what to do with her! I've heard that cats need to be kept inside for a few weeks, but no.idea how that'd work in practice.
How do I get her to use litter box?!? Best to start trying now, or wait till we're in new house? Scared of my lovely new carpets being pooed on 
Any advice gratefully received.