Yes you are right the cost of conversions has skyrocketed these days , the windows alone will frighten the beejeezus out of you if you buy them from VW . I bought a fixed side glass for a mate the other day for his VW T5 the glass only was $248 for a non genuine one but from VW from memory they charge around $700 plus EACH for their glass . So most conversion companies would either use the VW price to quote the job and then use aftermarket to better their bottom line maybe .