The best bit of advise i can give to anyone is to log your annual living expenses, i have done this for the last 3 years and expect to continye until i look to retire in 6 or 7 years time.
As basic as,
How much cas came into the household.
Hiw much cash went into debt repayment.
How much cash went into savings, investments.
Deduct the debt and savings payments from the total income for a rough cut figure of your day to day living.
Very rough cut but by my working out i need in the region of £26k per year in my hand to maintain my current lifestyle.
Obviously this will increase with inflation so i work it as a percentage of my total income,the aim is to keep this as clise as possible each year.