Eric (below) is a great resource for financing in your area. I believe the most common and cost-effective solution you'll find will be a HELOC (adjustable) to 90% of the appraised value. There are some fixed rate second out there, but compared to the time advantage you'd have on a HELOC set to Prime it may be worth the increased risk to ride out lower rates as long as possible. You'll pay a premium to fix in any junior lien.
If you have any questions, please let me know.
It is an interest only payment, and can close fairly quickly.
You can reach me at my office if you would like to pursue this.
Eric Nelson, III
Sr. Mortgage Planner
BRE # 01258488
NMLS # 120412