Travelling from europe to kathmandu.........

Hello people,

I'm researching the cheapest way to fly one-way from Belgium to Kathmandu around 2nd/3rd week of October.
Departing from nearby airports like Amsterdam, Cologne-Bonn Frankfurt or Paris is no problem.
Travel time is also not a real issue (i have no reservation with a trekking company) so taking multiple flights is OK but the overall flight duration shouldn't be too excessive.

I still have to be able to walk on arrival ;-)
I read somewhere on this forum from a Belgian couple who flew from Istanbul to Kathmandu with Air Arabia (http://www.airarabia.com) and that seems like a very cheap option.
It would cost 65 € to fly from Belgium to Istanbul with Jetairfly (https://www.jetairfly.com).
Then another 253 € to fly from Istanbul to Kathmandu with Air Arabia via the UAE, taking two more flights and a 12 hour total flight duration.
But if I recall correctly, the couple had to buy some transit visa at Sharja International Airport (UAE).
The UAE’s Embassy website in Brussels mention though that Belgian citizens on vacation do not require a visa.
Any one has any more information or experience with this route?

Finally, could flying to Delhi first and then taking a Delhi-Kathmandu flight be any cheaper?
And would you need a visa if only transiting through Delhi?