This on a cyclone fence surrounding a vacant lot.

Now what is it that inspires total lack of confidence here? That the sign is handwritten, when these dudes are supposed to be computer repairers? That the writing is uniformly bunched up to the right hand edge? That some of it is almost impossible to read? That if, even if I ignored all those misgivings, I should choose to have these people repair my computer, there is no way of contacting them written on the sign?