What age is it appropriate ?

Me (f17, 18 in a month) and my bf (m19) have been dating for over a year. I come from quite a conservative family who believe sleeping over and coming to someones house is an act of a serious relationship and that the couple will for sure get married. Though I agree it is an act of seriousness, I believe my boyfriend and I are quite serious. I am a person who doesn’t date for the sake of it, but dates for marriage. I seek a perfect life partner and have always dreamed of marrying my high school sweetheart.

My parents believe having my bf over would be over the top, mainly because my grandma on my moms side would judge, and i believe my mom is afraid of that. Both of my parents have already met my bf and are quite fond of him, joking around how they will be more crushed than me if we ever break up, so not liking him is not a problem. But, they won’t ever allow us to meet up either at mine or his house, which then gets tricky sometimes. I have been dreading but really wanting to ask them about when it would be appropriate for him to come over, so we can have a marvel marathon or something alike. I would also like to know when its appropriate for him to start sleeping over. Having him over i better for all of us because 1. It would heal my insomnia, i can always sleep next to him, 2. My room would always bee clean hehe, 3. And the most important fact is, my parents are home we wouldn’t do anything because they could constantly keep an eye on us.

What is your opinion on this? I apologize for it this post being so long and all over the place, i am very VERY passionate about the topic