Design a Sinking Fund System for All Your Irregular Costs

Car insurance, the boiler service, Christmas: predictable costs that somehow always feel like a shock. List your irregular expenses with cost and frequency, plus your income and seed money, and it designs a full sinking fund system, telling you what to set aside each month per category so nothing catches you out again. Quietly one of the most useful budgeting moves there is.

I want to stop being caught off guard by irregular but predictable expenses by setting up a proper sinking fund system. My known irregular expenses are:

{IRREGULAR_EXPENSES_LIST}

For each item I've estimated the cost and frequency. My monthly income is {MONTHLY_INCOME} and I currently have {AVAILABLE_SAVINGS} I can allocate to seed these funds.

Please generate a complete sinking fund design that includes: (1) the recommended monthly contribution for each fund, (2) whether each fund should be a separate account or a sub-account, (3) a priority order for building each fund from zero, (4) a master tracker template I can copy into a spreadsheet, and (5) rules for when it's acceptable to 'borrow' from one fund to cover another. Make the system simple enough to maintain long-term.