PayPal Information Security Engineer interview questions

Very unprofessional, the process was very lengthy, they took 3 months or so just to get back to me after the interviews to say they wanted extend an offer, but once we reached an agreement that both sides were ok with, I was told they gave it to someone else, no reason was given, when I insisted, they said they couldn't reach my pay expectations which is strange because we reached a mutual agreemment just a few hours before the email and we were moving forward in the process. They then proceeded to say it's because they couldn't offer a sign on bonus, which was not something I required but is something the HR person brought up as a possibility (I didn't know about) and I asked them to see if they could get me that as it could be good for my transition expenses, instead of coming back to me with a decision on the bonus and whether I was ok without the sign-on bonus, they said they moved forward with someone else after a few hours. Mind you, the offer itself was not good and not much different from what I'm already making. In essence, they gave an offer and then changed their minds. I say if you apply here, proceed with extreme caution, I never expected a company like PayPal to treat their candidates in this manner, they were also rather shady and didn't want to put things in writing, only over calls which is not something that I've seen else where. It seems to me as if they offered the same job to multiple candidates simultaneously and wanted to see who accepted the lowest offer first. People warned me about PayPal's practices but I expected better of PayPal for some reason. Be careful!