Well, I am not an expert, but you don't wait longer than 1 year. After all, the house is then exposed to weather, wind and rain without protection. I can't imagine that this is good for the stones.
Ok, maybe one shouldn’t wait forever, but plastering houses that are not completely dry is also not ideal. But that is somewhat off topic from the OP....
This house construction would be too big a risk for me. The builders who are skilled in craftsmanship can do a lot themselves. But that takes some time, especially since you still have to do the work yourself. But as already described, the risk is too high and there is a danger that there will be a half-finished house and a lot of debt.