Which investment has the lowest likelihood of being liquid?

 The least liquid investments are those which are difficult to buy or sell without incurring considerable expenses or enduring severe delays. Long-term investments that are difficult to quickly convert into cash or sell on a daily basis can be viewed as less liquid assets. 

The following are some examples of investments that are perhaps the least liquid:

1.  Real estate: Investment in real estate, such as commercial or rental properties, are sometimes less liquid since they might take longer to sell and may incur high transaction fees.
2. Private equity: Private equity investments are often made in privately held businesses that are not traded on a stock exchange, making it difficult to access the money invested or to sell the investment until the business is either sold or listed on an exchange for stocks.
3. 
   Collectible art: Due to the lengthy sales process and very high transaction expenses, collectible art is frequently seen as an illiquid investment.
   
4. Hedge funds: Hedge funds frequently set limitations on the timing of share redemptions and may demand a lengthy notice period before the redemption may occur.

In general, assets with little trading activity, large transaction fees, or limitations on when investors can sell their holdings tend to be the least liquid.

Investments that can't be readily sold or converted into cash without incurring large fees or delays are said to be illiquid. Contrast this with liquid investments, which can be easily purchased and traded on public markets and are typically thought to be more liquid, such stocks or bonds.

The fact that illiquid assets sometimes require a longer holding period than liquid investments is one of their fundamental characteristics. In contrast to stocks or bonds, real estate investments often require a longer holding period, and it may take several months or even years to locate a buyer and close a transaction.