Real Estate Investment Calculation?

I am planning to buy a house and sell it in 3 years. I just want to know if my understanding is good and my calculation is correct. So I put down some math here:

Assumption:
* Assume no closing costs nor other fees for easy calculation
* House Price: $383,000
* Down Payment (10%): $38,000
* Loan Amount: $344,700
* APR: 4.793%
* 3/1 ARM: 30 years
-> Monthly Mortgage Payment: $1,807
* Monthly Property Tax: $479 (Assume 1.5%)
-> Total Monthly Payment: $2,286
-> 3 Years Payment: $82,289

Let say if the house sold for $510,654 in end of Year 3
I want to know how much I made in profit:

-> Profit = $510,654 - $383,000 - $82,289 = $45,365

Am I doing the right math?

Thanks.

I just want to check if the calculation and thought process is correct, especially finance related. I don't know if there is any difference if I use 3/1 ARM or the one with interest payment only. I wonder when I sell the house, the difference in principle would have an effect on profit.

Add some more assumption:
* Assume zero cost when buy house (closing/points..)
* Assume zero cost when sell house (listing fee, agent fee, remodel...)

1st of all---- Are you watching the market???? Do you see all of the foreclosures out there. People took out arms and interest only loans and their interest rates shot up. You need to get a fixed rate for 30yrs. They are at a all time low. Also if you only put down 10% you will have to pay PMI (extra money out each month). Making money is one thing, but purchase the house like and could live in it forever. If you can not sell it atleast you will be happy. Even if you sell it for what you bought it for 3yrs ago you are still ahead. It is like paying rent and getting a bigger tax write off. Also don't assume what your taxes are going to be. Call the township or city and find out what they would be. Also do not forget home owners insurance. Lets get real!!! Your math says you will make over 30% profit on this house. Homes appreciate 1%-5% a year in a good/great market. The market is stuck in a rut. In three yrs your home will either be worth $400,000 or less (unless it is ocean front). Lake front homes have never gone down in value until 2005. They are still hitting rock bottom. Purchasing a home is more that money but your domain. Hopefully I answered your question and maybe gave you food for thought.

no. did you forgot to add how much it will cost you to sale this property, what about maintenance cost & repairs , what if buyers ask for any credits,how sure are you the you can sale for $510,654?