Hi Linda:
It would make the most sense to locate the property(ies) that you want to purchase in your first round of acquisitions prior to funding the refinance on your primary residence if you are worried about carrying the interest with no returns. As you know it is not an exact science though and shopping for investment properties with your cash already in the bank can open some doors that would otherwise not present themselves to you. That said, there are private lending products out there that can alllow you to shop for properties with a lot less cash in hand than you might think you need. Do you plan to buy and hold the new investment properties or rehab/ resell them right away? Do you plan to utilize any investor/ private money financing (debt) to go with your $600,000 to amplify your returns and increase your ability to buy?
There are second mortgage (heloc) products available that could save you quite a bit on interest carry costs if that is a major concern. That said, with the correct planning and budgeting you can plan for your costs in a way that the cost of the money is something that is not scary or concerning. Please let me know if you would like some consulting on this topic.
Thanks,
Logan Drew