I have received an offer to visit a lab for 4/5 months that could lead into a fully funded PhD. In the meantime I have other applications in the pipeline from which I will hear back in either a few weeks or a couple of months (just different educational systems).
I am excited about going to this lab but I want to wait to have all my offers on the table before commiting to a program. Also I am not sure yet if I will be able to develop in this lab the project I have in mind. However the PI of the lab is highly regarded in the field.
If I were to leave the lab I would want to leave in the best note possible not to burn my bridges with this person and institution.
I am sure the PI knows I might have applied elsewhere and also although it is likely that this visit will turn into a PhD there is also a small chance it will not.
What would be the best way to handle this situation in an ethical and correct way, and not disappointed anybody?
PS: I will get paid in this period but not as much as PhD student. Let me know if more information is needed.
EDIT: So apparently by the end of the visit I will present a PhD proposal, so I hope that at that point it will not be too late to answer other offers.