@Lee *********
. As Tod has answered more than once. You COULD be asked for proof of funds which needs to be in cash or travellers cheques. Having a return flight and hotel confirmation is a totally seperate requirement that if you never had you COULD be refused entry for if immigration required you to prove and you never had it.
So too answer your question, if your required to show the funds and you don't have it in cash or travellers cheques, a refusal of entry is highly likely and a return flight and accomodation, won't save your day.