We want to sell it and buy a new one. What's the best way to do this?   Pick up the phone and call a realtor to put it on the market. 

If this has been your primary residence in your name for the past 2 years then you can have a profit of up to $500K as a married couple  without paying any taxes on the sale.  If the home is only in your name then the profit is limited to $250K for the exclusion.   What you do with the money you get is immaterial for the last 20 years. 

Thank you Critter.-3.

So if we sell the home, there is mortgage balance of about $180000 in my moms name, that will be paid off. Will the money we get about $145000 be treated as our gains or my mothers? The house tax documents comes from the township in our name from the year of purchase.

Paying off the mortgage has nothing to do with your profit on the house ... but to get the exclusion your mom must NOT be on the deed.   It must be in your name for at least the last 2 years and be your primary residence 

Of course if the mortgage was in mom's name but the home was in your name you may have issues with the mortgage company since they will usually not let a mortgage continue if the home is not owned by the person who is on the mortgage document.   Hopefully you told them you did a quit claim back when you did it  AND  you homesteaded this property in your name.  Seek local professional assistance if this is not a clean title. 

In 2014 when we closed the mortgage for this house, the mortgage bank loan officer was present, we did the quit claim in front of them. They are fully aware of it. The only requirement they said is to add my mother as interested party on Home Insurance.

Me and my husband has been living in this home from the time of purchase, paid all mortgage payments, taxes, utility bills = all in our name. The quit claim deed is registered in the county office. Home tax papers comes in our name.

Then you have your answer twice. 

Does the quit claim deed being registered at the county mean that the ownership of the home is ours, even though we bought the home in our mothers name and she still has mortgage on it?

What professional should we contact? is it Mortgage person or a real estate attorney? 

Start with the closing company since they have to clear the title and then a RE attorney if needed. 

Thank you so much Critter-3. Appreciate it.