Long term capital gain on property

What is the name of your state? california
My husband and I bought two properties after the sale of our home 4 yrs ago. One for when we retire (more expensive and most of our equity was put there as it was eventually going to be our primary residence, it is used right now as a second home) and one in the city close to our work that we were going to sell in a couple of years when we retire (only 20% down payment from our equity, cheaper property). I have acquired an immune disease and would like to keep my same doctors therefore we pretty much need to sell both houses and consolidate and stay in the area close to my work. I know we have to pay long term capital gains (15% after May of 2003) but would like to know if we can change the primary residence to be the one where most of our equity went ( the more expensive home) as we intended to retire there full time but wont be able due to my illnes. Thanks

No, your primary residence is where you live most of the time.

Can I sell my second home, buy a second home (more expensive than the one I sold) then move to my second home declare the second home my primary residence (rent what use to be my primary home for a while) and then sell the house that use to be my primary home. And if so how long do I have to rent it before I sell it.

No, you cannot defer the gains on the second home by buying a more expensive second home.