LLC question and new investor inroduction

[Reed Olson]

Hi! My name is Reed Olson and my parents recently purchased three single family properties in Winona MN all directly next to each other and I am managing them since I work here. My question is first, they have formed one LLC and will that entity offer enough protections for all three properties or should they open three separate LLC's. Second I'm planning on buying one from them next year and house hacking it. Would it be better to purchase a separate property to house hack so they can have a larger investment portfolio or to buy it from them to maybe keep it less risky and more simple since I already know the property?

Thank you I hope the questions made sense!