What's on the first floor?

First floor has laminate in living and dining rooms with vinyl plank in the kitchen. Colours and textures are complementary. We live in a tourist town where homes like ours are often purchased for staff accommodation. The carpet is in decent shape but upper floors and stairwell have a few creaky spots. Not sure if the creaks will turn buyers off.

Oh - other neighbouring homes have a mix of flooring types. Do people want carpet in their bedrooms still?

Carpeting is still plenty popular in bedrooms in lower and mid range homes, even if it isn't "in". An exception is possibly is some warm weather climates where you see more tile and hard surface flooring.

I don't think you can go wrong with either carpet or laminate if you need a quick and inexpensive update, given the fact that you said your home could be purchased as staff accommodation. I nearly always prefer hardwood for durability and lasting style, but you'll pay a lot for that and won't see a return.

I like carpet for sound deadening, especially in a bedroom.

Your floor squeeks should be able to be remedied with a product called "Squeeks no More". Tom Silva, of This Old House shows a video of how to use the tool. You'll find other videos on You Tube. I'd go with carpeting in a bedroom. It's quieter and will transmit less sound to 1st floor. Staff in a tourist town might appreciate the quiet.

If you're in a cold climate, carpeting makes the floor warmer. Purchase a better quality rug pad to place beneath it.

I would never replace any flooring with carpet. I just don't care for it as it's too hard to keep clean and good looking. I'd put wood floors in a bedroom and add inexpensive area rugs that can be cleaned or easily replaced if you get to the point they really look bad. I've never had laminate or LVP but LVP seems very popular these days. I have considered it for my basement but not yet time to replace the beige carpet.

Have the current carpet professionally cleaned. Don't worry about the squeaky floor. It won't turn off buyers.

If these homes are used as staff accommodations, the buyer will simply be looking for safe, clean, and in good repair. I would spend my money and effort on neutral paint.

The luxury vinyl is a pretty good product. If you must install new flooring, this is what I would select. Just be certain to install it throughout the upstairs, not just one room. Visually, the continuity of material is pleasing to the eye.

There will be no return on investment if you install any type of new flooring, unless the old flooring was in such bad condition as to be a negative.