Moving in with your bf

Do you thing it’s appropriate to propose to my boyfriend after 4 months of relationship to move in together?

We have a close relationship, never been into a fight or something like that. Also, both of us is taking the relationship really serious( I met his parents, he met mines, along with other familiars and friends).

We are both financially stable (he’s 27, I’m 24).

He lived with his ex and it kinda end bad, si I feel like he has some cold feet about moving in with someone again.

What do you think about it?