We have the verb {yong} meaning "get in".

I can say {juH vIyong} without *having* to write {juHDaq vIyong}, since that would be redundant. It wouldn't be wrong. Just redundant.

Suppose now, I want to say "I get out of the house", and suppose that I want to use {yongHa'}.

Do I write {juH vIyongHa'} or {juHvo' jIyongHa'} ?

I tend toward the {juHvo' jIyongHa'}, since {juH vIyongHa'} sounds like "I get out the house".

But since I'm not sure, if someone could clarify this, it would be great.

You're assuming that yong is an inherently locative verb. It might be, but then again it might not be.

But let's suppose that you've got everything right, and that you really do need to use -Ha'. The object of yong is the thing you get into, and this object doesn't change when you undo the verb. juH vIyongHa' I undo-get in the house; I get out of the house after having gotten into it.

Although I can't claim that juHvo' jIyongHa' is wrong, I don't recommend it. This seems to me more like Going from the house, I undo-get in something unspecified.

-- 
SuStel
http://trimboli.name