Rent-seekers are ones who use force to enforce a monopoly price on their service by creating an artificial demand for it or a restricted supply of it. In effect it is a form of theft.

Everything beyond that is shades of it. If someone outbids someone else for the use of capital through honest acquisition is simply commerce. Those with more capital can outbid others who have less... supply and demand. That pricing signal tells producers they can sell their goods for higher prices, driving up supply and price down..

If the government comes in and legislates a price floor, however, the difference between the equilibrium price and the price floor is considered "RENT."