https://www.youtube.com/watch?v=KlNzeoyAokE
Before you ask!
"The real "mush-fakers" are men who not only sell, but can mend and make umbrellas. Wandering from street to street, with a bundle of old umbrellas and a few necessary tools under their arm, they inquire for umbrellas to mend from house to house. When their services are accepted, they have two objects in view. First, having obtained an umbrella to mend, they prefer sitting out doing the work in the street, in front of the house. This attracts the attention of the neighbours, and the fact that they have been entrusted with work by the inhabitants of one house generally brings more custom from those who live next door. When the job is terminated, the “mush-faker " looks about him, as he enters the house, in quest of an umbrella which has passed the mending stage ; and, in exchange for the same, offers to make a slight reduction in his charge. Thus he gradually obtains a stock of very old umbrellas, and by taking the good bits from one old "mushroom" and adding it to another, he is able to make, out of two broken and torn umbrellas, a tolerably stout and serviceable gingham."