Yes, now it is a bit of airport & handling back and forth at GMMX but at least with handlers one would avoid a last minute hassle like yours at GCXO, at the end it was a superbe trip: I enjoyed the reading, cheers for the write up and the stuning pictures !
I have one more question: in the first post, you spoke about places where you got cheap fuel.
Later, you posted things like:
Fuel around 1,8 euro/liter (no tax-commercial flight)/3,2 euro/liter (tax included)
Assuming that you don‘t deem 3.2 euros as „cheap“, what do you mean? For sure, yours was not a commercial flight (in the sense of „operated under an AOC“). So did you manage to just pretend it and everybody was happy with it?
In a few airports in Spain you can declare yourself as a commercial flight even if you have no AOC number. Only a few did not request it (in our trip Son Bonet and Lanzarote).
Bear in mind that a ferry flight or also a demo flight is considered “commercial” flight so it’s a bit “open to interpretation” rule.
Sounds strange…
Of course we paid the full price in our case ;)
But I heard by friends that it’s the same even in Ibiza and some other airports
Extract from a GA guide for Spain
“Fueling
Fuel Refuelling, cumbersome and bureaucratic, has been the source of some nightmarish stories. Allow plenty of time to refuel, and always aim to refuel on arrival. The main issue is that most transactions in Spain involve the use of a fiscal identification number called NIF (VAT ID#). Very often, foreign pilots are faced with a refueller who is not familiar with fuelling foreign aircraft, and insists on tapping in an NIF code (which invariably the foreign pilot does not possess). You have to insist repeatedly that you are a private foreign flight, and that bypasses a lot of the paperwork. On the fuel invoice there is a ‘Private Flight’ box to tick. It seems a lot of the GA aircraft in Spain are company managed or school owned, so the private avgas rate is the exception rather than the norm for most fuellers, hence the continuing confusion. There is a cheaper rate for commercial avgas, and in the old days it was quite easy to fudge it if you looked serious enough and had a company owned aircraft (or even a group). Now that they have gone all electronic, it is no longer as easy to waffle your way in to buy commercial avgas (or maybe I don’t look serious enough anymore). They now use a handheld terminal which makes a direct online check. If you are flying on business, and have an EU VAT identification number, there is apparently a way of using that or getting a NIF, but I would enquire a long time in advance! (In 6 order to get commercial pricing at CLH’s airfields (in practice most AENA airports) you need to have an ICAO 3-letter operator code and, unless that code is registered in CLH’s database, a proof of authorisation for commercial operation: AOC or other.)”
That used to work in Spain until maybe 10 years ago.
The word “commercial” would do it, and I even knew pilots who bought the cheapest possible uniform to help it along 
But it has not worked since; the pump man always asks to see the AOC, so short of photoshopping that (which is definitely illegal)…
It also used to work in Croatia; my most memorable one was 100LL for (equivalent of) 50 UK pence per litre at LDLO Again, not for a long time.
If you are running the trip through a VAT registered entity then you get the VAT back anyway, so getting it taken off at the pump is of no special value. It is getting the fuel duty taken off that makes the big difference – of the order of 30-40%.
I believe that Spanish flying text was written in 2011 by @podair who has been a contributor here in the past.
But it has not worked since; the pump man always asks to see the AOC
Well, apparently that is not quite the case.
Yeah I’m sure it’s going to be fixed in all Spanish airports soon (maybe it already happened).
But I’m 100% sure it was like the guide says in LESB and GCRR by the time we were there and we were dressed in very bad way so not really looking like airline pilots :D
