our worcester bosch junior has been playing up for the last month or so(fortunately weather has been mild and we ve got a gas fire and a power shower, but prefer baths in winter and showers in summer)sometimes we had hot water, sometimes we didnt, same as heating. it was 8 1/2 years old. we had a new vaillant fitted yesterday. our plumber did it for 1600 supply and fit. not too bad a price and it had to be done but could have done without that cost.still, hot water and heat is essential especially for someone like me who feels the cold these days.
the saying goes you get what you pay for and to the OP your mam might be better off getting a better quality boilerfor a few hundred quid extra. might work out cheaper in the long run.hope she gets her water/heating sorted soon though.