First deal done! Now should I get a loan to buy 3 properties?

[Account Closed]

Happy New Year!!! 

I wanted to share my project and get some feedback on my first deal

I'm 25 years and about 4 months ago my Mom and I bought our first real estate apartment at $90,000, small condo two bedrooms near a college area that generates $517 per room (including utilities). 

I have been considering using our equity in the property to get a loan and expand our portfolio 

I have been looking at this 

http://www.b2rfinance.com/products/portfolio-pro-l...

Up to $300,000 to buy 2-3 more units 

-How much should I have in savings? 

-What kind of properties could be best? 

-What are some of the most common not obvious expenses in buying three properties (time, repairs,etc)? 

-Is there any Forecasting tool that you recommend to see what kind of return should we expect? 

Thank you!