Don't throw up a red-flag
You stated that his mother and adult siblings like you, are these siblings of his or his mother. He could very well be an old soul, the fact that his place is a mess explains that he is a confirmed Bachelor, his mode of transportation... old junky things highlights he is a man that honors getting the most for his buck, he is frugal, or he ascribes to the if it ain't broke why replace it... so those are not things to trouble yourself with; however, if the adult siblings are those of his mother, then you know that he is an old soul, think about it, if the adult siblings are his, his +20 yrs old friend equate to his comfort level. However, what bothers me... how has he gained the Insider Track on you... is it because you FREELY shared with him, if so, no need to be alarmed, you set this atmosphere based on _______________-what??
So let us not get the hairs on the back of our neck standing because you gave a little too soon, too quick. I can't venture to say why he has not declared his love for you, why he does not speak of a future with you... because I do not know the terms, the conditions this relation is built upon; however, he knows. So ask him to spell out the relationship, what does he want/expect and do not be afraid to share your expectations/wants. Lack of communication is never good. Open up to him, ask and thus you shall rec'v.