Balancing the size of the return with the size of the risk can be a tricky thing, but ultimately the decision to invest should not be "how much can I make" the question is always, "will I get my investment back" Without this sort of assessment, no matter what the promised return, an investor can find him/her self in troubled waters.
Private investment is different from institutional investment because the individual takes full responsibility for their own investments.
The typical investor is an institutional investor who gladly hands over his lump sum to a fund manager and the investor gets an aggregate result each year based on the funds ultimate results.
This is typically fairly low, but the fund is relatively safe because it tends to apply its capital reserve to blue chips.
Private investors are typically institutional investors that decide to split off part of their lump sum, maybe 5% or 10% and decide to apply this fraction to more aggressive investment activities.
This is a fairly wise move and spreading the risk this way is an effective way to maximize returns without losing the farm.
Some typical places a private investor may wish to apply their more discretionary investment income is in start up investments.
To do this an investor will typically let his lawyer or accounting firm know they are in the market for a start up presentation and this leads to a viewing of a new idea or business concept.
Typically a private investor is asked to sign a legal instrument by the entrepreneur called a nondisclosure document.
This form reserves the entrepreneurs copyrights and keeps his confidential business information safe from investors who decide against investing.