You're joking right?
Repair is one button press when you do it yourself, using an item that you can stack 99 of in one inventory space, for a more effective repair than using an npc, vs spending 5 minutes running to an npc to just have it put to a lame 100%.
If that's a PITA to you you might be playing the wrong game as there's literally a hundred more painful things I can think of.