When owner-occupied you could go FHA with 3.5% down, but there are limits as regards the loan amount (limits depend on the region). You could do owner-occupied with an investment property when "hous hacking". Do a search here on BP, for instance.
On the other hand, the higher the loan, the higher the monthly payment will be. So from an investment return point of view it might not work when looking at the figures. As you are hopefully aware, the mortgage payment is not the only thing you will need to factor in with respect to monthly costs. There is vacancy, repairs, management, CapEx etc and with an FHA at 3.5 you would also have MI as an added cost.
So typically, most investors - if they even finance at all - go with 25-30% down. And this is what most lenders will, indeed, require from you.
Regarding the interest rate being higher for multifamily: that would be true when looking at 5+ doors because then you will be in the commercial lending spere. And they are, typically, more expensive when looking at the interest rate. If you don't go over 4 doors then you are still in the realm of conforming loans, i.e. Freddie/Fannie and then you have the "normal" interest rates. These will, however, always be higher for investment properties compared to owner-occupied. At least this is what I have seen over the years.