Hi Wenderlynn - have you asked proprietors of similar businesses in the UK who they use? It seems like you would need the same coverage as a therapist + additional coverage for work you do offsite as a designer/installer.
Subtropical desert (Köppen: BWh)
Elevation: 1090 ft Annual rainfall: 7"
Wait for it ... wait .... wait .... NOW! Pafiffle! A perfect tiny ad!
Tomatoes! Ha! Anyone can grow that. Amaze your neighbors, grow your own shirt!