Remember Marxist concepts of class are dialectical. They're not rigid, static categories. The class system is also global, so it's not possible to determine someone's class only by looking at their day-to-day life.

Just another instance of class mobility. If for instance this person has to rely on the rent for their main income but works a casual job to supplement it, then their interests lie in protecting that rent.

Lenin cathegorised people belonging to other class but also needing to sell their labour to live as "half-proletarian". Usually he meant peasants having too little land to live from, but i think it can be also used for this kind of small time renters.

They key to that was that such situation is usually not stable, capitalism eventually will shove those people to become fully wage labourers, similar to the petit bourgeoisie and small scale landowners.