Single Musicians: 
Violin, Viola, Cello, Flute or harp i.e.
for a wedding ceremony, accompanied by organ or piano, or as a solo.
One Strolling Violin.
One Classical or Cocktail Piano.
  Harp
  Keyboard/Piano Solo
Trumpet

Duos:
Violin and Viola. Sax and Guitar
Violin and Cello. Sax and Flute
Two Violins. Keyboard and Guitar
Flute and One String. Keyboard and Vocal
Piano and One String. Vibes and Vocal
  Flute and Guitar. Organ and Vocal
  Harp and String Heralded Trumpets
  Harp and Flute String
  Sax and Horn Jazz
Sax and Keyboard    

Trios:
Violin, viola/violin and Cello. Harp and Strings
Violin, flute and Cello. String
Trumpet, trombone and clarinet  Jazz
Violin, Cello and Piano.    
Keyboard, Bass & Strings    
Harp, Flute and Piano.    

Quartets:
The classic string quartet.
Quartet - Violin,- clarinet, trumpet and trombone.
Brass Quartet - Two trumpets, French horn and trombone.
  Harp and Strings
  String
  Jazz

Other Ensembles
Keyboard, Bass, Drums & Strings
Can include Sax and/or Horn and/or Strolling Violin(s).
Jazz ensembles 5 to 10 piece
Harp and String Quintet
  Vibes, Bass, Drums, Sax Horn & Guitar