We like (or are addicted to, depending on who you ask) Starbucks and make sure there is a half pound or more available for every arriving guest.
If logistics allow, it is also a very nice touch to leave some sugar and creamer in the refrigerator for guests to make their coffee their own. We own multiple units and buy the sugar in bulk and stock fresh half and half from the grocery when we can.
We have tried multiple machines and have chosen a very basic drip coffee maker for its ease of use, durability and most importantly auto shut off feature. Filters we like are these disposable ones.
Although our bias runs strongly towards coffee, we also like to leave a few varieties of tea, both caffeinated and herbal for guest who prefer that method of caffeine uptake.
The caffeine ritual is not complete without a beautiful mug (that is also dishwasher and microwave safe) Below are some we like that have held up well:
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