I was terrified that I would build this RV and not be able to get insurance for it once I was ready to fly since I was such a low time pilot (100 hours). I was pleasantly surprised that I can get insurance and all they want is one arm and a first born child :) Joking aside, below are some estimates of what you can expect to pay for annual insurance costs to cover an RV-10. Rates tend to fluctuate from year to year so this is as of mid 2011. Usually sign off from a CFI or 10 hours in type is required to initially get the insurance.
For me, I got quoted around $3400 for the first year and the cost should drop 'significantly' after the first year, is what I was told. What is significantly? Not sure - maybe around $1k. I was told having 50-100 time in type is the key to drastically lower rates. Get a quote of your own for more precise costs of course. This is just to give ball park estimates to keep in mind.
Here are some other quotes from other RV-10 owners courtesy of Matronics:
$2795 for $140K hull, $1M/$100K liability.
Pilot: commercial/instrument/cfii
2000+ TT/1000+ high performance/20 hr time in type (at the time
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$2,800
$150,000 Hull
Discount for TAA
I had >700 hours last year with 150 in RV-10…..Commercial/Instrument ticket
I insure myself and my flight instructor..when I added him it did not affect my premium.
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$175,000.00 hull and 1 Mil liability for $2295.00
Update 2/9/2012: more discussion on the topic here: https://forums.matronics.com/viewtopic.php?t=88356