If they're cheap and available, there's a chance their work might not be up to your standards (depends on what your standards are).

I don't think they are in Houston city limits but they have Houston address so I just applied taking the chance so we can help the tenant. 

Is the debt you are seeking reasonable for current market conditions OR are you looking for amazing debt that has a 1 in 20 chance of happening?

(You already missed the chance to triple your money in a month). 

I would suggest getting a survey if you don't already have one (if you purchased the property with a mortgage, chances are you may already have one in your pile of papers from closing).

Since I don’t have any experience yet I want to build good habits and thus have a better chance at building great relationships with contractors because I understand that’s an important factor in being a great real estate investor.

The only $500k houses that would likely even have a chance of cash-flowing would be distressed or low-end properties in extremely expensive markets.

There's a very good chance your niece will disappear as soon as she see's you're serious.In the future, don't even rent to friends or family.

https://www.biggerpockets.com/blog/2015-01-14-rental-property-manager-how-to-chooseHave you had a chance to find any property managers in your area?

I feel like a house hacker has a better chance in this situation.