Other scammers could be contractors that you seek. Once they start major renovations on your house, they leave you high and dry. They demand that you pay all or half up front, as a policy. Some will even ask for money for materials that they don't buy, and simply keep the money.
They never finish the job and the victim is left with an unfinished renovation and without money or the supplies they thought they had bought.
Furthermore, contractors have scammed homeowners by buying low quality supplies and materials but telling the homeowner that they are high quality, and charging them much more than what the supplies are worth.