Long term capital gains is 15%. Since you have written them off over the years, your capital gains will 100% of the selling price minus the cost of repairs you have not completely written off.
As far as your primary residence, you have to declare it as your primary residence for 2 of the last 5 years and you do not have to pay any capital gains nor do you have to reinvest it in another residence. I did not know there was $$ limit as TMagda mentions.
So if you do not mind moving every 2 years you can escape paying any capital gains.
There is another approach called a 1031 exchange and a reverse 1031 exchange. This entails selling your property(s) and buying another like and similar property for more than the selling price of the other. This has to go through a lawyer or campany that holds the money for you. If you want more details on this, email me at
[email protected]
I've been into rental business for 15 years and have another 11 to go so I watch this pretty close.
Best bet though is to find a good real estate attorney in the area to completely fill you in.