Apologies but quicker as a list. These questions are more about a long term stay than just a fortnight.
Has the manager been in post a while? Do they have a deputy? What is staff turnover like? Is the night staff a separate team or does everyone change their shifts like nurses? The answers you want are a strong management team with a well trained settled staff.
Use all your senses. Eyes -look for residents with clean hair, none with talon length finger nails, no stains on clothes. Look for signs of good hygiene practice and lots of clear instruction on notices for staff and visitors Nose Sniff out whether there is a stale smell in the dining area, do the sniff test too for toileting smells. Basically you just want neutral clean smells. Ears Listen out for kindnesses and gentle talk between staff and residents, listen out for how many noisy residents they have and how they keep these residents settled and entertained. Touch Covid allowing, just check that things work to get a sense of their equipment if it is maintained and not tired and broken. Taste Even better if you get a chance to drink a cup of tea and see if they have home made scones in the afternoon. Some places do, some don't
Ask about which room, is it sunny, does she have a place to sit and look out the window? (These may not be important to her) Ask about entertainment and her routine. What's a typical day going to be like and how would they tailor that to her needs and requirements.
Above all look past the decor but into the eyes of the people.
The staff should look like they want to work there and the residents should look like they feel at home rather than be zoned out and empty. My DM has been in three care homes. One which was shut down by the Care Commission. One which was v posh but unaffordable and the one which she is in now which has lots of pluses but went through a very tough spell with four managers in a year.