They will look like an obvious scammer so it weeds out the ones who know about scams.
They tell obvious lies and see if the other person will let the lie pass. They test to see if the victim, if male, is sexist, a sexist victim doesn't think they can be outsmarted by a woman. They play victim. They flatter. etc etc
Interesting. Well I just found out this guy has been scammed by a phillipino woman before. Guy bought the woman a farm in Thailand then she dumped him.
So this is actually round 2 for being scammed. At this point I want to believe it's some kind of mental illness.
It would take a certain personality to believe that a random international internet stranger who is much younger, very good looking, flirty and generous with flattery would develop an instant adoration and sexual attraction for someone they’ve never met.
I think there might be a subgroup of victims who fall for it out of loneliness, even if they may suspect something is not right they continue because it’s respite from their loneliness. But sounds like your neighbour is not in that group, and just has a lot of ego.