We are NON-EU residents and need to know how long we can stay here

Hello,
we are having great difficulty trying to apply for residency although we have property in Malta and Gozo. We didn't purchase at the right amount as we were given misinformation.  ( 275,000 is the min).
we are trying to figure out if we come here to stay for 90 days and then just leave for a week and go somewhere else in the EU and then come back if we will be allowed to stay in Gozo for another 90 days. how long do we have to leave for in order to come back and stay and do we need to leave the EU or just Malta before we return. 
we also thought about setting up a company, sole proprietor to be able to try and get residency. Does anyone have any suggestions. As a US Citizen, we are finding this to be very difficult as we have no Maltese ancestry.
thanks,
Jackie

Best look at 
https://identitymalta.com/citizenships-expatriates/
for up to date info.

I understand you may need to be here to apply anyway.
As I understand it, if you leave Malta and return then that resets your 90 days.
I did see this on a website but cannot find it now.
Perhaps consult the US embassy here.