CAWBY, easy spelling, simple to research - YEAH, RIGHT!
The Cawby surname probably holds my personal record for number of spelling variations. As I recall, before I took off to Salt Lake City to search for Cawby origins about 6-7 years ago, a fellow researcher had mentioned that he come across 80 or so spelling variations. Leaders were Cawby, Caubey, Cauvey, Cavvy, Corvey, Cawey, and Causey, mostly from Kentucky tax records.
Martin Cawby Sr.'s first marriage bond had two spellings of the name in one document.
I was extremely lucky in finding a gold mine of family info early in the week at SLC. Background information from a book on German settlers in the Catawba Valley in North Carolina and deeds provided most of the details. Those sources also upped the number of spelling variations considerably.
Most of the previous variants made an appearance along with Cabi, Cavi, Caby and similar forms. To top it off most of the new spellings also had a G-factor: Cabi = Gabi, Cauvy =Gauvy, etc.
All totaled up, I think there were over 120 spellings combining Maryland, NC, Kentucky and Indiana sources. Incredible!
Have I mentioned that when researching a surname you need to think of every possible spelling imaginable? After that, go for the unimaginable.