I don't know what options you are including but here's what mine would have cost. NOT counting the bike.
$9195.00. Basic kit
These are the options that mine has.
$1045.00. Floorboards
$1095.00. EZ Steer
$1095.00. Reverse
$1195.00. Aux Fuel Tank
$ 495.00 Chrome Wheels
$1795.00. Paint (one color)
$ 425.00. Paint (floorboards)
$ 325.00 Trailer Hitch
$16665.00. Total
PLUS Installation. I don't know but have been told about $2000. So that brings the price, if you already own the bike, to $18665.00
I didn't own a RSV so my decision was easy. The fact is though, there are a number of RSV trikes on the market for far less than what it could cost to convert yours. So unless you have a very low mile RSV that you just can't stand the thought of parting with, I would look around for a used one. I paid a few thousand less than that for the 2005 that I just bought and it even included a color matched Bushtec trailer. It had just over 28,000 miles on it and also came with a handful of other options including riders backrest, highway pegs, passing lights, tank bib, etc..
I see them on the market between $12,000 and $15,000 for the trike without a trailer. Deduct what you could sell your bike for and you would be out much less money just buying one that has already been triked.