At the start of summer I did this small patio for an old woman in her 90's. This week (2 months later) I get a phone call from her saying she wants to see me. I go around and she tells me when I finished the job, i'd left the outside tap on. Damn! It was attached to hose pipe and I'd just turned the hose off. She said in the night it had popped off and was spraying around in the morning. Thankfully she wasn't on a water meter. Lesson learned. She also said the resulting water spray had washed the sand away I'd put between the patio flags and because of that the weeds had started to grow back through. I went out and checked for myself and the sand was all there between joints, it hadn't gone anywhere. Anyway, I apologised for my mistake and then cleared the patio by hand of weeds again topped up the bits and pieces of jointing sand I'd disturbed. It took me about an hour. A more sturdy jointing mix would have been preferable but I did this job for cheap for a friend and the joints were very thin so kiln dried sand looked OK. They're also very uneven and would need re-laying properly I would have thought before doing anything like that. When I'd finished she asked me if I would consider maintaining the patio on a regular basis. I said I'd get back to her. Would that be something people would take on? Is it worth it? I'd guess it would be just me calling round every 8 weeks or so in the summer mainly, taking the weeds out and spraying a weed killer down? I'm guessing one or two hours work to keep on top of it? Most people would just do it themselves but she's in her 90's and despite being in great condition for her age, it is something she won't be able to do herself. Would you take this on or is this a gardeners job? What sort of price would you charge for this? Which weed killer would work and have people had success with? Any advice would be great.