Re: Make it, or buy it?
Bread
Obviously always make my own unless unable to. Store bought bread is laden with chemicals and preservatives and really very bad for you. Bread needs to be long fermented. You'll only get that from an artisan bakery or from making your own.
Passata
I make batches of homemade passata with nothing but fresh plum tomatoes, garlic and basil. Store in portions in the freezer to make pasta's and chillis.
Granola
A delight in summer. From a base of muesli oats, which I toast, I add hazelnuts, pecan nuts, almonds, cranberries, dates, dried apricot nibs and raisins, all bound together with healthy coconut oil and a little treacle to give that slight gingerbread flavour. Great with yoghurt and fruits.
Washing Powder
Recent commercial washing powders are hugely alkalinic and burn or irritate many people's skin. An unhealthy option.
I make batches of my own using £1 bags of soda crystals and completely natural soaps which I grate. Finding truly natural soaps without bad parabens in is difficult but the Faith In Nature website has many with great scents. Lavender and Rosemary are 2 of the best for washing powder.
Cold/Flu Remedy
Never buy over the counter remedies like flu capsules as all they do is greatly prolongue your illness and make it worse with the paracetamol or equiv element. I blitz entire lemons (pith, peel and juice) in a blender with big chunks of fresh ginger and a little hot water to make a super healthy flu busting pale yellow concentrate. It keeps in the fridge for a week or so. I use it like orange squash, a little in a mug with hot water and a little honey for sweetness. The vitamins and goodness in the pectin quickly kill throat bugs.
Chutney/Jam
Wife used to make many 100s of jars of various chutneys every Christmas but hasn't done so for many years now. It's just not cost effective to make your own unless you have access to a free windfall of fruit.
Aside from that, like many others I make all my meals from scratch using fresh ingredients. Never ever buy ready meals and only very very occasionally have take aways.