First Duplex- debating options in finance and LLC

[Robert T.]

Hello, and thank everyone in advance.

So I live at home, but recently bought a duplex in a great location that works well in all aspects.  I plan on buying the property in my name as a primary residence as I get to put down 20% instead of 25% conventional; and I get a rate that's .5% lower than investment rates.  I also plan on renting both sides out, but having the possibility of falling back there as a plan B-C if this spring does not produce a primary residence for me. 

So another layer is this is purchased as a primary for finance reasons, but is intended to be an investment. I plan on buying a primary this spring time and putting it in my fiances name. She can carry the note and add me onto the deed. Can I add the duplex into the LLC at any time or do I have to wait 1 year? I was told I can only purchase 1 primary a year, is that true?

If for instance I have zero debt, and my income could carry 2-3 mortgages; and that still be <50% of my income; Would there be a problem with me scaling a house every spring for the next 3-5 years purchased as a primary and moved into a LLC? Or would it just become an investment property when I purchase another primary every year. After it's an investment it can then be rolled into an LLC?

If someone could maybe give some insight into pro's and con's do's and don'ts I'd appreciate it. 

Thanks, Rob