Primary Residence Mortgage vs. Investment

[Ademir Zukic]

As I have discovered, a Primary Residence mortgage is able to give you some of the lowest interest rates as compared to an Investment Property Mortgage. I assume much of this has to do with what the persons intention is with the property. I understand you are able to rent other rooms as long as you are a resident of that property. If someone is looking to get a property with the intention of renting out the whole thing in the future, is this something that is even possible with the mortgage type they have? Is there a minimum amount of time they have to be in it to before they are allowed to do so? Would they have to eventually (assuming they fixed it up), do a cash-out refinance and obtain a new type of mortgage allowing them to rent it out? Does this vary per lending institution or is there actual legislation involved? Curious to see if you can help me with this, thanks!

PS: Any sources would be appreciated!