I have 3 solutions for Keeping Vlad out.
1. I had activated him just before going into my real household. He doesn't have garlic immune, and very weak at sunlight. So plant 5-6 garlic plants in front of the front door, and Vlad wouldn't be able to manage the smell. I tested with my vamp sim and human sim. The green effect of garlic doesn't appear to my human sim but it does to my vamp sim even though he has garlic immune perk. So it will work to Vlad too.
2. My vamp sim completed Vampire Lore skill when he reached up to Grand Master level. He visited Vlad, and he made 'drought of reconfiguration' drink. Then I switched over to Vlad, then let him drink it. I purchased 'tamed thirst' perk for Vlad, then back to my vamp sim. I've never seen Vlad's visit since that time. I've seen Caleb just once.
3. Make one of your household into vampire. Vampire sim doesn't need to go sleep as far as vampiric energy is enough. No no..vamp sim can go sleep too. There was Caleb's visit after midnight while my all sims were in sleep. My vamp sim woke up from his coffin, then Caleb just gave up hunting and returned home straightaway. There were no garlic at all in the house. But if you grow lots of garlic plants, Caleb also wouldn't come. It's also good for active vampire because he or she doesn't have to go outside for hunting. Just ask for permission and drink plasma of active human sims. Once they are bitten by vampire, other vampire is not allowed to bite them for 12 hrs.