@Mary536
Since I'm not sure what kind of guests you get, this is just based on my personal experience and preference..... but I think a fridge, toaster, electric kettle and microwave are more than sufficient for a kitchenette.
I would not offer a blender, oven or roaster or slow cooker of any kind to guests - I wouldn't trust them to use these safely and clean them properly after use. If you are planning to buy any new appliances for guest use, make sure you buy ones with some sort of built-in safety feature that prevents overheating and do not get too hot on the outside surface.
There was a recent post from a host that his guest left the oven on for several hours. I'm sure this type of scare has happened to all of us at one time or another, but guests using unfamiliar appliances (that don't belong to them) are higher risk - in my opinion.