Does anyone know the story of a human guy entering an old house where he meets a vampire? ...

I believe your looking for Moon Phase here is the link
http://www.mangago.me/read-manga/moon_phase/

Sorry it's a yaoi ! :(

http://www.mangago.me/read-manga/vampire_kiss/
this one maybe?

is it this??

http://www.mangago.me/read-manga/koyoi_wa_kimi_to_chi_no_kisu/