That is a task I would only do by the hour. Some houses are a 1 hour job but not many. Some take all day or enough of a day that you can’t get a second one in. The only thing for sure is unless you get into a job where there is government housing and all the houses are all identical (we have done that) there will be no 2 houses alike (we have done more of these). That said, it is difficult or more like impossible to say how many you can do in a day. Another big concern is the travel time between jobs. We have a job we’re the travel time was near an hour one way.
We got out of that part of the business for a lot of reasons. Money was one of them.