shaun/lor

hi does anyone know what the max length of stay would be on a visitors visa type 48 or 48r they say that over six months and you should state your reasons for this, what would be a good reason for say wanting to stay 1 or 2 yrs. would the renting out of a property in uk constitute having funds to exsist in oz for this amount of time,
im just taking precautions in case the mother in law decides she does want to visit us, after all. cheers shaun xxx