The two types of trips are vastly different. A Cessna 182 or Piper Dakota would easily for the first but not for the second. In the realm of singles, a Piper Saratoga or Lance would work nicely but with Pipers you're sitting on the floor (ie low seats). A Cessna 206 or 210 would work too. If you're looking at twins, there are more options. A Piper Seneca II or even up to a Cessna 340 but operating costs are a lot higher too. An old school Piper Twin Commanche might be a good balance of fuel economy, range and useful load...

There are a lot of answers to your question and the cheapest one might be to rent a limo for the 100 mile trips and charter a Citation for the longer trips.

C9