My DS loves blackberries so I bottle about 20ibs of them each year. All it takes is old jam jars and sugar syrup. He has them with pancakes through the winter.
I make jam from damsons and greengages that grow wild here, and rhubarb & ginger jam - free rhubarb from next door🙂 About 15p a jar.
I slice & freeze cooking apples in season for quick pies and pastries in the winter. Windfalls that I don't use go in a tub by the front gate for neighbours to help themselves.
I buy 4pt containers of milk, decant them into 1pt plastic bottles and freeze until I need them. Sterilising bottles is quick & easy. Milk is 85p a pint or £1.49 for 4 pints. I buy large loaves of good quality bread, cut in half and freeze in plastic bags so bread is never wasted going stale.
Each year I make up a 3ltr jar of blackberry and apple gin and leave it to steep for 18 months. Makes a fabulous liqueur for the Christmas after next.
I reuse plastic bags (Amazon etc) as daily 'bin' bags to cut down on plastic use. I freeze leftovers. Make soup with veggies that are getting past their best or with the carcass of a chicken.
Use bar soap and very few cleaning products - just washing up liquid, white vinegar and bleach.
Any garden prunings thicker than my wrist are cut up and added to the log pile. Helps with the heating bill and saves taking them to the tip.
I've just sold ds'school uniform - blazer, sweaters, ties, sports kit which has paid for clothes for 6th form.