First property and first mortgage, is 4.125 average or should I have shopped around? Shockingly, my lender quoted me the same rate for a 30yr fixed, due to some income based First Time Homebuyer incentives.

That is a very good rate. Take it!

For owner occupancy or investment? Definitely very high for owner occupancy by me. a friend of mine literally just locked in at 3.5 on a 20 year yesterday.

Of course it depends on your credit, etc. No one will be able to give you an accurate answer with a very broad question, but it's definitely not good if you are owner occupant with a 740+

Go with the 30 year.

Agree with Scott. Your payment will be lower which will help with DTI for other future property investments.

I closed on my first purchase (primary residence, 3 bedroom and renting the other 2 rooms to roommates) one month ago. 5% down on a 30 year conventional with an 805 credit score, though my lender gave me a 2% grant at closing so I really only put down 3%. My initial interest rate was also 4.125%, though they offered to give me another $1350 at closing if I bumped it to 4.25%, which I took. 

Since I ended up putting so little down on my primary and have savings left over, last week I was pre-approved for 25% down on a duplex out of state at 4.75%. 

Originally posted by @Derek Luttrell :

I closed on my first purchase (primary residence, 3 bedroom and renting the other 2 rooms to roommates) one month ago. 5% down on a 30 year conventional with an 805 credit score, though my lender gave me a 2% grant at closing so I really only put down 3%. My initial interest rate was also 4.125%, though they offered to give me another $1350 at closing if I bumped it to 4.25%, which I took. 

Since I ended up putting so little down on my primary and have savings left over, last week I was pre-approved for 25% down on a duplex out of state at 4.75%. 

Wow so you were able to be preapproved only one month after closing on your 1st property? 

I got my rate down to 3.875 on a 20yr fixed conventional, for my owner occupied first property. I'm in somewhat of a bind now bc my DTI is over 40%. This limits my buying power for my 2nd property, when I decide to shop 12months from now. I'll have a Roomate paying half of my mortgage but I've read that some lenders won't let you use "boarder" income to help qualify.

How did you get preapproved so soon after your 1st property? Was your DTI low enough after your 1st property?

In a year or less, my goal is to put myself in the best situation to purchase an owner occupied SFR or Duplex, most likely with FHA due to the low down payment option. But I'm starting to see this goal as unattainable bc of the mistakes made from my 1st property.

Thanks for the insight

@Bo S. it does come down to DTI, yes. My lender knows I have more than enough in savings right now to cover 25% down and a year's worth of payments on the loan, so they pre-approved me just a couple weeks after I had just closed on my first primary residence.

While roommates may not count as income in a lender's eyes, what they will do is help you expedite your savings for a year or however long it may take for you to have enough cash saved up to help you qualify in the near future. 

Originally posted by @Eric Hardt :

For owner occupancy or investment? Definitely very high for owner occupancy by me. a friend of mine literally just locked in at 3.5 on a 20 year yesterday.

Of course it depends on your credit, etc. No one will be able to give you an accurate answer with a very broad question, but it's definitely not good if you are owner occupant with a 740+

 Lol