Most builders are only able to make a profit because they build many homes at once and get materials at a steep discount due to the quantities they order.It's not like flipping, where the property is there are you are just improving it, you will have many costs such as connecting the property to the local utilities which could be inexpensive but can also be (more likely) crazy expensive, it all depends on the land you purchase and the proximity to current local utilities.The lure to jump in can be hard to resist, but take your time and find the right property. 

I have the property list but I do not know how to find their phone numbers for large quantity of properties.

How sufficient, secure, and stable is her income source?

First the disclaimer: one turnkey property (or DIY rental) will not a sufficient income make.

Hey Travis,You can buy another investment property right away using conventional financing assuming you have sufficient down payment, credit, and down payment/cash reserves to qualify for another property.You can use your rental income to help offset your monthly PITI.

The issue comes when you're LLC isn't established enough to have a decent and sufficient track record yet.   

As you get experience, work your way up in the quantity of your apartment complexes.Being able to use the cap rate when adding value gives you more "bang for the buck". 

I have excellent credit and sufficient funds. 

Also I think that it may allow us to aquire a larger quantity of traditional home loans since in the future my DTI will be much better ;) ...

The only large quantity of properties in my under 200k price range are studios.