Don't forget that this is all an insurance issue.  If you are really
confident in your skills, you are perfectly free to fly your plane without
insurance.  That is what I did, but I had 70 hrs of tail drager time in the
last 4 years. While I did not have any TD time in the last 2 years, the rest
of my flying skills were very current.

I'm not sure when you last flew a tail drager or how many hours you have in
them.  I'm not sure when you last flew any aircraft at all.  I can't blame
an insurance company for requiring you be current before they cover you.
There is no question that flying is a skill that fades over time.

I am happy to let you have some time in the right side of my plane (leaving
me the brakes), then later in the back of your RV-4 (again leaving me the
brakes).  But when you are ready to climb into the front of your RV-4 for
the first time, I probably won't be in the back - I won't be any help to you
back there. All you can do to get back up to speed is helpful.  If you don't
want to sell the 182, then maybe get it flying.  Then you don't need to  pay
any instructor to get yourself lots of practice.  Having your landings in a
tri-gear down pat will mean that during the tail dagger practice you can
concentrate on ground handling and transitioning to the RV.

In my opinion, when you are ready to risk your life to your flying skills,
risking the value of your aircraft is a small wager.  I wouldn't be too
worried about insurance, be worried about whether or not you are ready.  If
you want it long term, that is fine.  It will be easy to get insurance after
you have a good bit of time in your aircraft.

Dave