Some Vray issues (not expert)

I am having a very slow process getting the results I want with vray. I followed a vray guide and got good (same as tutor) results with just the sun in barcelona pavilion. Then I tried adjusting the sun to get a nice inside shot. It was not easy, tried spotlights and played with intensity, direction, length but that didnt work as easy as I thought. Then I switched to a somewhat strange system having rectangular lights facing upwards and downwardsand, got a pretty nice even render and tried using the same system for another interior. Now the rectangular light doesnt seem to work almost at all. A lot of parts gets too bright seemingly without any reason. I also switch the intensity for the rectangular lights but it has very little influence.

I guess I am mostly wondering, how would you start putting light in a scene like this?

You should upload your scene here, you can replace the objects with cubes, so somebody could get a chance to help you efficiently. Sometimes, a small detail like unchecking “use GI” will completely change the behaviour.

Allright, I am rendering offline having my laptop online but when I finish rendering, Ill upload something.

But I was hoping to get a recommendation of what lights normally are easier to manage. I thought the rectangular light that was working well in the last scene was easy but for this new scene it is not so I just switched to dome lights. (FOr example). Perhaps it is more tangible also to use actual lumens instead of “intensity” that depends on the size etc? Stuff like that.

For me, the best way to setup a new scene is to replicate as much as possible the reality.
IES spotlights, rectangular lights with realistic settings, etc
From there, when the tests renders are close to what I want, I start to optimize. Replacing the sun with rectangular lights in the windows, etc

Allright, but rectangular lights does not exist in reality except led panels which few people use? But how do you do the correct sun angles etc if you change the sun to windows?

I found rec light to best do an interior space but I am having this issue now when the light is in the scene, it creates a white rectangle so I do it in passes with different lights and overlap in photoshop. It is quicker than trying to get perfect lighting in a big scene with different light sources but perhaps not ideal.