No pay for common wall

We and several neighbors agreed to build a common wall between our properties her in Southern California. One neighbor agreed in writing to have 1/2 of wall on his property. and to pay $1000.00. After it was built he has refused to pay the $1000.00. He does benefit from the wall. We had a verbal agreement on price. We have written agreement on placement. I plan on going to small claims for breach of contract for failure to pay, but there is another legal principle involved. What other arguments can be made?

[annjd]

That is basically it--he agreed and then did not pay. You should prevail.

[buyproperty]

You have rights to put a legal case on this problem. You have agreements papers then you should not compromise. According to property investments laws your questioning is absolutely perfect. You can carry on.