DIY or NOT DIY that is the question.

I try to evaluate every job in my house that could be a diy task, for instance when I moved in I tried to get as much painting done before I actually moved in, and would make the house more to my tastes. I soon realised after I moved in that there were other jobs needed doing, not all decorating. The heating in the house was a gas fired back boiler behind a gas fire in the living room, I would guess put in in the eighties, and because it was in the living room it had to have ventilation, so an air brick was in the wall of the living room, not ideal as the room subsequently was cold from draughts.
The gas fire was not the most attractive feature in the house, and the hot water was supplied from a tank in the airing cupboard, so pretty high on gas usage, all in all not great. I admit this was not a task for me to take the tank, back boiler and fire out, I realised this was definitely a job for a plumber/heating engineer. The diy job I did do while the plumber was doing his bits was putting a fire surround and hearth in after the back boiler and old gas fire were removed, so fortunately I got the plumber to put a replacement fire in. I also got him to put a radiator in the living room as well, so I do not use the gas fire too much as there was not a radiator in the living room.
Needless to say I blocked up the air brick very soon, as the boiler is now in the airing cupboard with an outlet through the roof for ventilation. I also took the opportunity to paint the walls in the living room as well. So estimate if you can do a job and if not do not be afraid to get someone better qualified to do the big job as invariably you can do some diy job as well.