Landlord wants a bigger cut of my profit

Occasionally I look after peoples dogs when they go away. I had an agreement with my landlord to pay him an extra $20 a week in rent whenever I do this. I do a pickup in the yard at least twice a day. They are inside with me or at work or out with me most of the time. He has no responsability for them what so ever and he says they never bother him.
I am minding a Pug puppy at xmas for a couple of weeks and the owners were so grateful they have offered me twice the money I usually charge. Now my landlord wants more money on those weeks, because of my bigger profit. He hasn't said how much yet. All he has said is something about "getting a cut on that", This morning he said he was telling his dad about OUR business venture and we will have to chat about it soon.
I do not want to be unfair. I just need some advice on what IS fair.
Just for the record, he is 50 and has not worked in many years and there is no physical or mental reason for this. He says he just doesn't want to. He has no social life or friends, therefor no networking. His only income is the rent I pay him.
By Peanut 8 years ago :: General
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