I am engaged to a widow. He has usufruct to his house, we plan to sell and buy a different home. He does not plan to give the heirs their portion of the house, he wants to put it toward our different house.

Can he do this?

I do not wish to agree to this, since I have a home that I am paying for and will be all mine when it is over. I do not have a chance to do that with my widower putting his children's money toward our future house. :(

Do you have any recommendations?

So he has legal right to use the property, is it limited or restricted to his life time.

He will have to follow the rules of the will. If he merely has usufruct then he does not actually own the property to legally sell it,

Who is the listed owner on the deed, or is it still in the estate.

I advice that he cofirms with the probate attorney that they used for the will. And do what is legal

There are too many things unknown here. I'm assuming that the property was partially owned by his wife. Who was it left to in the will? Why does he only have usufruct?

I have not seen the will, however I have been told he and his children (2) have inherited the wife's half of the house. He has more ownership than the children. The children are both above the age of 18.

Well then simply put he can not just up and sell that half if they also have ownership in it. If he manages to then they can sue him for their part. He should really go back and look at the will again or have it read to him again with explanations for everything including definitions of words and what his abilities are.