There were 2 points to my initial response, though evidently I expressed these ineloquently.
My first point was that it isn't realistic to expect a professional convertor to match, on a like-for-like basis, the price achievable by a DIYer. I accept that you did not intend to imply this, but that's what I inferred (from your initial post: "...gives you an idea what a conversion company should be charging").
My second point was that, like most things in life, there are conversions and there are conversions. If, for instance, you were to add/substitute...
- a bonded Reimo 3000 bed
- leather upholstery
- leather A-pillars, B-pillars and door cards
- Alcantara lining
- a hot water system (not a hot tub )
- an off-grid lithium power system
- air-ride with 20" Rolls Royce wheels
- a full ABT body-kit
- an upgraded sound system
- etc
...then your conversion budget would be irrelevant, if not misleading.
Please be assured that I am in no way dissing your conversion. I have the upmost respect for those that self-convert, if only because I know I don't have the skills!