@Yiping2 I don't take bookings over 14 days myself, and have a home-share listing, not an entire place, but hosts who do often recommend doing much more than checking in with them by phone.
It can save you a lot of grief to set up quick weekly cleans, linen change, etc. for long term guests. That way if the guests are slobs, you don't end up with a huge cleaning chore that takes all day when they move out, and if they are abusing the place and causing damage, or have snuck in a pet, or extra people, you can read them the riot act or boot them out before they destroy the place.
It can also make the guests more respectful, if they know you or the cleaner will be coming in once a week and seeing how they are living in there.
But this is all something you need to set up and state when guests book. A time to do the cleaning should be set up so it works for both you and the guest.
Some hosts provide basic supplies like soap, tp, shampoo, etc for the entire long term stay, some leave a starter pack, like enough for a few days, and guests are expected to provide for themselves after that. It sort of depends on your price point. If they've gotten a sizable discount for a longer term booking, it could be financially unviable for you to keep them supplied with everything, especially if they're the types who go through a roll of toilet paper a day or drink 10 cups of coffee a day. Again, this is something you need to decide beforehand and make clear in your listing for bookings over XX amount of days.
It's usually enough to just tell the guest to let you know if they need anything, to report any issues with appliances, water, etc, right away. Checking in with them the first day to make sure they found everything alright and are comfortable is pretty standard practice, but no need to keep checking in with them. Maybe once during the stay, if you aren't going to clean and see them on a regular basis.
