Captain Beefheart's Magic Band had two bassists in the early 1970s: Rockette Morton (Mark Boston) and Orejón (Roy Estrada).
Boston also played guitar.
Estrada is in prison.
My son used to have a Crafter SA-TMVS with a Kent Armsrong lipstick pickup, a piezo in the bridge, and an L.R.Baggs preamp. It was around £280 new in 2010ish. Bargain guitar.
A (major or minor) third higher is common, e.g. Everly Brothers.
Personally, I never got much beyond shouting in unison while playing the root note or walking fours.
Good luck.