Regarding Anders Larsson, I think that he was the children's uncle (their father's brother). And I'm wondering if the "old man" Per Ollofsson might be the children's maternal grandfather - (their mother's father)? It would make sense that an uncle and grandparent might have been the ones involved in the inventory. I will see if I can find anything on that.
Anders Larsson was their uncle, "farbroderen" can't mean anything else. And the theory about old man Per Olofsson being the maternal grandfather makes lots of sense. If possible the trustees should be family and since there was an uncle available he would probably represent all of the children if there was no more relatives to do the job. So Per Olofsson should be a relative and a grandparent still going would be perfect. And with Anders Larsson coming from the husbands side, Per Olofsson coming from the wife's is even better. But of course exceptions happends all the time...