If two duplexes and SFH are being sold in one sale, advertised in the listing as 5 units, is that commercial, or is it still residential because it's 3 separate houses? I am watching my market and I noticed a newer listing that's in my price range, but as I'm looking for my first investment, I don't know that commercial is the way I want to go right off the bat.

If all are on one property, one parcel ID, then 5 units, commercial.  If they are on separate parcels, but simply being sold together, then 3  separate residential units, for financing.

It is being listed as one unit on one plot of land, so that would make it commercial then. Thank you.

You might want to check the county records to be sure. Find out if the tax assessor has them listed together (all the same tax ID#) or separately (each address has a tax ID#). I would not rely on what the listing agent has put in the mls.  There is really no harm either way, but if you do have separate parcels then you might have the option of selling them off individually later. Although if you have them financed under one loan then you would need to have the lender agree to release them individually to do that.