I never had luck with K Cups. I use an Aeropress for espresso-strength coffee and use half and half as my creamer. I've found that the peppermint flavor is pretty easy to get with any store-bought syrup, but the rich dark chocolate mocha flavor is what's so hard to replicate. It's unique to Starbucks.
When I worked, I drank one cup in the morning and sometimes one more in the afternoon, which was completely sufficient. Now that I'm staying at home with my kids, I'm exhausted all the time and find myself drinking at least 3 cups a day!