Mom moving into our new house with us

any money she gives you would be a gift unless she is also put on the title (this should not be done unless you want her to be part owner) 

if she makes a separate gift of $19K or less to each of you, she will not have to file a gift tax return. that is the money should go to each of you and then you turn around and use the gift to buy the property.

if she gives more, she'll have to file a gift tax return or if she makes a joint gift of $19K or more. it is unlikely she would have to pay any gift taxes unless she has used up her lifetime exemption - something north of $13 million. you do not report or pay income taxes on the gift. 

There are no tax implications for you if your mother gives you money as a gift and you use the money to buy a house that you will own, or that you and your spouse will own. If your mother gives you more than $19,000 in 2025 she will have to file a gift tax return, Form 709, but she will not have to pay any gift tax unless the total of all gifts she has given in her lifetime is more than $13.9 million. She could also give up to $19,000 to your spouse without having to file a gift tax return.

If your mother will be a part owner of the house it will affect tax deductions for mortgage interest and real estate tax, and tax on the profit when your eventually sell the house.

You used the words "our" and "us," and then "I" and "me." If you have further questions please clarify who you mother will give money to and who will own the house.