1. How to make my house 'cat fun'!? 2. How to make my cat 'own' different peices of furniture?

I live in a house hold where both my housemates work and are only home in the evenings and weekends. I am usually the person that is home more days than not, meaning that my cat is allowed to use the outside front  and back enclosed decks during the day (these decks are not outside but rather just an extension of the house). I just recently got a casual job which means that some days I won't be able to let her out onto these decks because she wouldn't be able to get back in (due to locking up the house). She is an indoor cat who sleeps almost 24/7 but takes refuge under her couch located on the back deck, outside. (My first post on this site, reflects her attachment to this couch and I am worried she may get upset with me or down if she can't access it on some or consecutive days.)

I have a few  possible solutions for this and would like some thoughts/experiences/suggestions:

Solutions so that she does not get bored if she is indoors:

- Invest in some cat trees/climbers; she is an older cat, and did not have cat climbers in her previous home. Do you think she would use these and curb boredom?

Solutions with her couch: *I have taken the cushions off her couch and made a smaller hidey hole on the front deck so she can have her scent in both locations/feel safe*

-I wouldn't like to move the cushions from the front deck to inside but could if it made her feel safer as then there would be nothing on the front deck

- Move the couch inside all together. I have avoided this so far as I fear she would be under it all the time. when she is inside for the evening after being out on the deck under the couch she is calm and loving. She is also used to a routine and almost expects to be let out to the couch in the mornings..

- Ask for real estate approval to put in a cat door on the back deck so she can come inside freeley

Suggestions on how to make our house inside more entertaining would be apprecieted

And,

Is there anyway to make my cat get more attached to other pieces of furniture inside the house so that she doesn't ALWAYS want or need to go onto the back deck/be content with being indoors a bit more

Side note,

I am her new owner and the only piece of furniture that is her's is the couch and a few blankets gifted from her previous owner. Her blankets are on my bed which she loves.

If you can get permission to put in a cat door I think that would be the best solution. You don't want to make too many changes to her routine all at once. A few years ago I screened in my back patio and put a cat door in the door from the living room. The cats love it.

Since I posted this, my housemates and I decided to bring the couch inside and plan to do this tonight. We figured it would be best as she can have access to her beloved couch and because the real estate denied us for putting a cat door in.. do you think she will be happier in the long run with this arrangement (I imagine she might be scared at first with all the noise wheb moving it but our intentions are not bad!), I would just hate to think that she is home alone without it when everyone is at work. At least this way we wouldn't have to worry and she can come and go to it as she pleases..?

Does she like cat nip? Maybe put cat nip on the places you want her to lay on.

She has a few cat nip toys which she ignores haha so I'd say no but as long as the couch movement is a permanent thing I'm sure she will be okay.. it is HER couch after all and we are doing it for her we are in the process of moving it, it's still her first month with us so we hope that once everything is settled including ourselves she will enjoy having her couch inside even if she is used to it outside on the deck. We get heavy rain here in Brisbane aust so havinf her couch inside would be better so she doesn't get drenched when under it. Please let me know if something I've said is a no go maybe from past experiences anyone else has had..

We have moved the couch only a few inches on the deck to get her used to it facing a different direction before bringing it inside too..