A potential PhD supervisor wants me to visit campus for an interview before I know if I'm accepted I've been in correspondence via email with a potential PhD supervisor who has agreed to take me on. After a few emails back and forth and polishing my proposal with his guidance I submitted my application per his instructions. He suggested we interview after I submitted my application. It's been a little over 2 weeks since I submitted. He suggested either a Skype interview or a visit to the campus. Visiting the campus would mean I would have to book some plane tickets. They're relatively cheap since it's within the UK but I'm also on a budget and don't know if I'm going to get accepted or if the interview is required for a decision on my application. I suggested a Skype interview and then during the interview we could arrange a visit on campus but he countered with an offer to just visit the campus during the last week of the month. I was confused so I agreed I could visit campus but asked for him to clarify or provide some guidance on the application process and never heard back from him. I still haven't bought plane tickets and am not sure how to interpret this series of events. Should I just explain my situation to him and ask for a Skype interview? When I agreed on a visit I told him when I would be able to fly out but haven't heard anything so I'm really not sure about buying plane tickets. It all seemed like things were going along smoothly but now I'm very confused. Any suggestions?
The solution here is honesty and candor. You should explain that you would like to visit the campus, but that your financial situation doesn't allow it at the moment. Any reasonable person would either drop the suggestion of a campus visit, or find some money to pay for your travel expenses. Any other reaction would be a red flag.