Guppy has been paying his own hotel expenses and turning out without getting any payment, so keen is he to earn a contract.
The former Leicester and Celtic wideman has played in all of Leeds' pre-season games.
Guppy is set to complete his trial spell in a final warm-up game against Hibernian at Easter Road on Saturday and then a final decision will be made.
Guppy said: "I'm not used to being on trial but I'd love to stay at Leeds. Given where I've been over the last few years I think I have a lot to offer. It's just a case of persuading the manager."
The former Leicester and Celtic wideman has played in all of Leeds' pre-season games.
Guppy is set to complete his trial spell in a final warm-up game against Hibernian at Easter Road on Saturday and then a final decision will be made.
Guppy said: "I'm not used to being on trial but I'd love to stay at Leeds. Given where I've been over the last few years I think I have a lot to offer. It's just a case of persuading the manager."