1. is still possible to put down 5% on a conventional loan? Yes, however the requirements may change depending on how many units the property is.
2. are there any 1st time home buyer programs? or grants - typically yes, however be wary of these. Speaking from the ones we typically see in FL, the 1st Time HomeBuyer programs tend to carry a higher interest rate and stricter requirements to qualify. We often see them requiring a minimum 660 credit score and many require you to pay them back if you refinance or sell the property within 5 years. they're typically for owner occupied properties only.
3. what are the avrg rates for 790 credit score and no debt? max down payment i can do is 5 to 10%. That depends in part upon your debt to income ratio, if you plan on living in the property, and how many units the property is. this is the ratio of your gross monthly income to your monthly obligations (credit card payments, student loans, auto payments, etc.) For a single unit owner occupied home, you can probably expect to see rates around 2.5% but if you are not living in it, then you're more likely to see rates around 4%.
4. is it true that conventional loan is stronger than a FHA? Sellers do tend to view Conventional loans more favorably than FHA. However, there are advantages and disadvantaged to each program and it's just a matter of finding which one will best suit your needs.
5. what is the avrg pmi on a duplex around 350k to 450k ? That really depends on how much you're putting down and debt to income ratio.