In personal finance, total investment simply refers to the amount of money that a person has in a given place. Finance information website The Motley Fool refers to total investment when explaining capital gains. For example, if you invest $20 in 100 shares your total investment is $2,000 (and if you sell those shares for $30 each, your capital gain is $1,000).
Starting a Business
When starting a new business, the total investment can be the projected cost of beginning the business (this use comes up frequently in franchises, where the parent company has a history of previous business ventures and a good idea of what a new franchise will cost). After the business has been established, the total investment refers to the actual amount of money that the owner and investors spent establishing the venture.
Similar to beginning a business, total investment can refer to the total amount of money put into a project. For example, the World Bank's website defines the organization's use of total investment as "the sum of investment in physical assets and payments to the government" for each of the countries that the bank works with.
People use the phrase in many different ways and usually give the parameters of the statement (for example, "My total investment in the stock market comes to $10,000"). People also refer to the total amount of capital--another word for money--in a venture, investment or business.