Should I top up my special account so that I can get $1500 per month on CPF life? I’ve emptied my OA to fully pay up my 4 room flat. Do I auto qualify for CPF life annuity?

You should look into your future plans to see if you have any liquidity issues as well. On top of cash - SA, you can also look into your future OA - SA. Personally i feel that having CPF life annuity should be the backbone of your retirement plan but it SHOULD NOT be your only source of income for retirement. I will suggest reaching your FRS first before looking at stocks/reits.

You need to build up your savings again and get your emergency fund up as soon as you can.

After that, if you have no immediate needs for liquidity and also depends on your preference for cash liquidity or not. Save and invest.

Have a look at your Medisave account to see if it is almost at the Basic Healthcare Sum. Provided that your CPF contributions (yours+employer) does not exceed the CPF Annual Limit, you may consider topping up the MA with cash to hit the BHS. The voluntary MA contributions are tax deductible. And once the BHS is achieved, the MA contributions are redirected to the SA account. Hence your SA will also increase and the year end interest payable on MA will also flow to SA if the BHS is maintained. This pays off in the long run as the 4% interest rate is almost guaranteed. But locks up your cash to a fixed rate.

If any leftover cash after this is done, you may consider directing those funds to investment in the stock market. However the returns depend on which instruments you use. You may want to look at roboadvisors for simplicity. Or if you are interested to learn, you may consider DIY your portfolio. Potentially can get higher returns than SA interest rate.