Need help finding a sustainable setup for me and my puppy (condo living)

I’m a first-time dog owner with an 11-week-old shih tzu puppy. She’s been with me for about a week and a half and is doing really well overall. She's sweet, understands my rhythms, but also a little feisty!

I live in a high-rise condo. Right now, her main zones are:

• a square pen (~70x70cm) in the living room, where she eats, sleeps, and plays
• semi-open wash area where I take her for potty (pee pads)

This setup is working for her. She’s comfortable, and we’ve only had 3–4 accidents total so far. She sleeps through the night except for a midnight potty with some zoomies. I let her explore my bedroom and home office once a day after successful potty trips, but those rooms still overstimulate her and she’s had all her accidents while exploring.

I don’t currently have a crate. I tried introducing her to a travel carrier for nighttime sleeps, but she strongly dislikes being inside it and it’s a slooow work in progress. Because of that, I’ve been sleeping and working in the living room with her, which isn’t sustainable long-term.

Here’s what I’m struggling with:

• Her current pen is too lightweight. She can push it around when she wants attention, which requires my 24/7 supervision.
• I need to return to working in my home office and sleeping in my bedroom

For her first year, I want a setup where she can: play/eat mostly in the living room; be safely contained while I do daily tasks; sleep in my bedroom at night; still use the wash area for potty, then later transition to outdoors when fully vaccinated.

My plan:

• a sturdier same-sized pen in the living room as her main daytime space for eating, playing, and relaxing
• a smaller crate (or pen??) in my bedroom for nighttime sleep and naps
• she can hang out with me in my home office when she's calm, but I want her to also be comfortable staying in her pen or crate without me present

I'm under a tight budget. Before I commit to buying anything else, I’d really appreciate advice on whether this setup makes sense and how to do it right.

My questions:

• How do I transition her to feeling calm and relaxed in my bedroom, especially at night?
• She’s used to sleeping in a spacious pen. Will a smaller crate stress her out? Instead of a crate, can I just do a smaller pen + bed in my bedroom?
• Does this setup sound reasonable for a condo puppy, or am I missing something important?
• If she’s left alone for a couple of hours in the future, should her main living room pen include a potty area?
• Will having multiple zones (living room + bedroom + occasional home office) confuse her, or does consistency matter more than location?

My goal is to keep things simple, consistent, and comfortable for her while also making daily life workable for me. Any advice from apartment/condo puppy owners would be hugely appreciated!!