20% down Vs. 3% and how it affects finance.

[Erik Larson]

Hi real estate enthusiasts. I am working on my first home purchase. I plan to buy within a year and live in it for the next 1-5 years. After that time I would like to rent it out. Until now I have been researching using only 3.5-5% down on an FHA loan for about $500,000. I would like to know how 20% down on that purchase price can change what types of loans, monthly payment, maximum purchase price, DTI, etc. I would also like to look at a SF Bay area median price of $720-750,000 as well. Any comments are greatly appreciated, looking forward to working with you! Thanks!

I also need to know if there are any laws or rules against refinancing an ARM before it matures, adjusts, or amortizes. Thanks! For example, can you buy with an ARM 5/1 and refinance to a Fixed Rate before the rate changes?