every city you mentioned has its good and bad area's
concentrate on locations(streets/suburbs) that have local amenities and understand the type of customer you wish to be renters
for instance if its near a hospital, aim to promote the house to doctors(high income)
or if you are looking to air BnB look for locations near tourist/entertainment/sports venues
as for you looking for investors... well if you cant show experience and funding records of already doing real estate, no one will invest in you, especially not strangers you/they met on the internet.. basically you mentioning lots of locations around the world means that you are not even bothering to want to manage the location near your own personal location. this scares people as you want to just take money and not have responsibility. it also shows you have lack of a plan, by just spouting out random cities
if you cant even get a relative/friend/work colleague/your own bank to invest in you and instead you want to seek stranger investment. it starts raising more red flags, especially with the other things said about your lack of understanding the area's/customer types