You need to figure out whether it’s worth the closing costs and such for $30K in cash.
No one (likely) will loan more than 80% on an investment property.
Ask around about HELOCs. They have lower closing costs, but will likely be at a higher rate.
You also have to consider that the additional monthly payment will cut into your cash flow. Maybe this is ok, maybe it’s not. It’s up to you!
You can do a HELOC up to 80% LTV . I got one last year with Pennfed, no closing costs and no appraisal since they do a desk appraisal and if it's sufficient they wont do a regular one. If it isnt then you'll be out $300 but that's it. Keep in mind it will be a 12 yr variable with a balloon payment due but that's not bad at all even if rates increase. Good luck!