i understand your frustrations and concerns i to have 2 boys aged 2 and 4 but a step daughter who is very distructive also.
i am sorry to say that while you have done a fantastic job at raising your own children to behavie in the manner you approve of you have to realise( and i don't mean to sound nasty) that you did not raise these other children they have lived their many years doing what they are without repremand and now you come in to change that you should have expected some ajustment time or simple rebellian.
it is for the biological parents to sort out how to deal with this issue, you need to lay down the expectations you have of the soon to be step children and then you fiance needs to have his say, then you need to compramise on some ground rules and what will be the disciplan action plan if these mutual rules are not followed. please take into consideration the up bring of the soon to be step children and maybe even ask what they and your own children would like from this soon to be blended family you may have to eases up in some areas but be stronger in others. if you want your relationship to work you need to work together remember you are going to be a step parent not another parent let the bio parents do their jobs but be supportive and help where you can remembering to take time for your self and your own children.
sorry if this sounds harsh but you wont to live togther and make things work so you need rules that reflect the outcomes you want, but consider that your trying to blend two very different households things are going to have to change for that to work you can't make someone elses children be the same as yours you didn't raise them.
hope this helps and didn't sound to harsh.

I would never tell you "boys will be boys," but I will tell you that men can be idiots. What seems so obvious to us - if you pee on the floor, clean it up! - never even occurs to them. And dirt? Forget it. They are incapable of seeing it. The boys may be destroying your house, but your husband is allowing it to happen. There's not a thing YOU can do about this, short of throwing them all out, unless Dad gets on board and takes control of his children. The problem is, I have no idea how to talk to Dad without him thinking he and his boys are not welcome.

Unfortunately, the youngest is halfway to adulthood and the others almost there. You know you have to start young. My 9yo son unloads the dishwasher, helps fold clean laundry and put it away, feeds and waters the dog, cleans the dog poop out of the yard, rakes leaves, helps out with his little sister, empties the bathroom trash and is expected to keep his room tidy. His little sister is four and we're already working with her, teaching her to put her dirty clothes in the hamper, put her dirty dishes in the sink, put her toys away, take her dirty shoes off at the door instead of tracking up the floor. These boys obviously didn't learn it as youngsters, so it wouldn't occur to them to clean the pee off the floor, to put the toilet seat down, to clean up spills immediately or to tell you if they've broken something. They weren't "trained" right from the beginning! (And man, do I ever pity their future wives!)

I think it's time to be frank with your fiance and hold nothing back. You love him and want to be with him, but you cannot allow everything you have to be destroyed by his children. That he needs to take them in hand, let them know what the expectations and rules are in your home and warn them of the privileges they risk losing if they don't start pitching in and respecting you and your home. And most importantly, if you are to have any chance at a successful marriage, he must support you, he must present you as an equal to his boys, he must back you up in discipline and he must set a good example for his boys by showing them the proper way to conduct themselves.

~ Anne ~

"Love, having no geography, knows no boundaries."
(Truman Capote)

I too have raised my 3 children right from a young age to respect your own property and the property of others. If something has been broken in the past, they were the first to admit it and tell you how it happened and say they were sorry. My step son's on the other hand (been a stepmom for 3 yrs) have never had to respect anything. They are 14 & 11. I have a lot of antique furniture that has been handed down in my family for over 150 yrs and it has taken a beating. I remember one time sitting down and crying because something was spilt on my buffet and they didn't inform me....why anything liquid was put there is beyond me. My kids were not even home, so I know for a fact it was the stepson's that were responsible. To this day they have not owned up to it and they probably never will.

Hubby is constantly telling them and showing them respect, such as putting the toilet seat down, cleaning up after themselves, taking your muddy shoes off at the door, but every other week you have to retrain them. It is a constant battle. They don't do it at home so without thinking they just carry on like they are at home. I agree that it is the parents fault for not teaching them and correcting behavior from day one. A saying I heard one time replays in my mind again and again......you can't make them the parent you want them to be....so there is no sense in trying!

Hang in there and work with hubby.

My SS is not destructive but he certainly knows nothing about helping out or putting the seat down!! One of the reasons my SS doesn't want to, nor does, come here anymore is because I told him 6 times a day to 'Please' put the toilet seat down & please close the cupboard door...he said that was 2 many rules...can you believe that?? So I must say that it drove me nuts telling one child 2 things 6 times a day, so I can not even fathom how frustrated you must be with 3 of them!!

Thing is it was also MY home and MY nice furniture, but I simply would not tolerate it in MY home but sadly the outcome is that my SS feels, I pick on him, mainly because the other kids knew the rules because they had been PICKED on for many years before SS's arrival. Because your kids know the rules, you will always seem to be favoring your kids or picking on the step-kids..it's a lose/lose for you.

So here are your choices, deal with it or say NO WAY and boot them out into the yard and reprimand them every time they do something destructive. Alot of people say leave it to the Bio parents...I disagree, you have tried that and it ain't working, and it's your stuff, so protect it yourself...you will be evil either way.

Catch xx
*Mean People Suck*

I used to get sick at the way my SD would think stuff-even her person was clean when it was far from- SD had to be reminded and re-taught constantly how to clean self, rinse tub, dishes, and still is working on organization in her room, but I did once stand down wind from BM and found out where she was coming from. It takes time to change anyones habbits especially if it isn't expected at both homes but it did happen for us( whether fluke or just SD wanted her stuff respected) we have grounded both of our children from clothes( when 3 weeks running it was over-run and no one brought it down while I am on lifting restrictions) after they were washed they were stored- I haven't had that problem again(probably better for girls)' I have cleaned our sons room using a hefty and did throw out quite a bit- for every item he was grounded a day(43 total) from getting anything in the way of toys, candy treats and such.
I know this sounds rough and might be but if something hadn't changed I would've hired a maid(another great idea) or you could price new furniture or cleaning for the current stuff and watch how serious he becomes when he realizes you're serious!
Hope it helps a little! goos luck.