There is no minimum stipulated for a 175 but it is obviously in your own interests to research what living costs will be and be prepared to have ample to allow resettlement as many new migrants may find it not so easy to get work initially.
My partner is doing a 47SP permanent partner visa (we have been together 12 years and he has been out in 2002 on a temporary residence visa). It says that we need to bring enough money to enable me to support him/us for 2 years. Are there any guidelines as to how much the minimum amount we should write on the application? We intend to get work as soon as possible after we arrive.