How to apply SWR concept if there are big payments upcoming?

Hi all, appreciate the sharing here and on Telegram that has motivated me to make this post for discussion.

TLDR:

Planning our earliest retirement date and trying to apply the SWR concept.

• If we retire before our BTO in 2030, the Karsten calculator shows ~94.2% chance of success at 2.4% SWR (2.6mil) when including negative cash flow for down payment + 25-year loan.
• Without the BTO payments, the 2.4% SWR leaves me with a 99.6% chance of success.
• With the BTO payments, I need a 3.3mil initial portfolio to have a 99.7% success rate. (1.88% initial SWR)

Is that the correct way to model this? Does that mean we should aim for 3.3mil to be 'safe'? Should we just stop fantasizing and wait until the BTO down payment is settled to take a look at the numbers again so this problem doesn't exist? 😅

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Longer version, thanks for your time:

I'm 30M, wife is 28F. We do not have a 'retire by XXX' date, just hoping to see what is realistically possible and whether our planning has been sound or anything else we need to consider.

We've been tracking my expenses for the past 2 years, are in companies that do not allow taking extended AL. We do take short trips now, but looking forward to travelling for longer periods and working on our hobbies.

• We currently spend ~45k annually on ourselves, combined, tracked over the past 2 years, and it has been relatively stable. We predict spending 60k annually due to longer travelling periods after retirement.
• We give a total of $2000 to our parents monthly. I marked this as inflation-adjusted in Karsten's calculator for a duration of 50 years. (excluded from above)
• Only big expense coming up should be housing (260k in 2030 downpayment + renovations; 2.6k monthly for 25 years)
• We probably won't have kids or pets. Parents have sufficient in CPF for their own retirement and are sufficiently self-insured.
• Our current portfolio is 1.5 mil, split into 84% equities, 5% gold, 11% cash investments.

  • Equities are 60% VWRA and 40% SG Banks. We intend to keep it at this ratio by topping up the shortfall going forward.

  • Cash is SSB and savings.

  • We invest ~8k monthly consistently. Based on this and assuming 6% growth and no layoffs, we should have ~2.4 mil right around Q1. We would need extra ~4 years to reach 3.3mil instead, based on averages.

Some key questions I'd appreciate insights into:

- Is this the right way to approach planning? Why is there such a big difference in 2.6mil and 3.3mil with the estimates? I indicated there that planned retirement was 01/2030.

- Do we need to factor in insurance? We are now fully covered, but most of it is CPF; there's little cash required, and that's included in the ~45k currently.

- Should we factor in an allocation to SA continually so there is CPF Life to cover us in our later years? Our CPFs currently add up to ~150k and is not included in the above.

- Is there a world where I'm complicating the cash flow and we actually have a lower FI number?