cut one’s coat according to one’s cloth 量力而为
A：Can we buy a house of our own, dear?
B：Not now. We have to rent house for a few more years.
A：The price is reasonable at present. What if prices rise?
B：My salary isn’t very large at the moment and we have nowhere to borrow much. We must cut our coat according to our cloth.
A：亲爱的，我们能买自己的房子吗？
B：现在不行。我们必须再租几年房子。
A：现在的房价挺合理。如果房价上涨该怎么办呢？
B：我现在的工资不高而且我们也没有地方借钱。我们必须量力而为。