How to build friendships without messing up houses

Now that I've got my dreamies back and they have original houses and clothes, I'm going to try and keep them like that. I was like, "Omg my girl Fuchsia wants a bug I'mma go get it for her so she'll love me!" Then she junks up her house putting it on display. So how do you build friendships with the villagers without screwing up their clothes or houses? Do you only do certain quests for them like the fruit and not the deliveries which are often clothes they change into? Is that possible. I feel bad turning down my fav villagers and making them sad but c'mon quit trying to sell me your furniture- I want you to have it! lol
Also is getting your friendship up with them how you get their pictures?

I give my villagers the occasional bugs and fish, but it tends to be the ones that look pretty when on display like the goldfish and the Popeyed fish. I tend to just redo their houses in Gracie furniture when they ask for things, or with marshal I send him spare sloppy furniture I have. You can still build up good friendships with them just by delivering parcels for them, visiting their house/visiting you. I didn't do much for Deirdre when I had her, just wanted her pwps and still got her picture when she left. Just from occasionally visiting her and bringing her fruit

One thing I do is I will give them customized furniture of things they already have. Like Julian has a few regal pieces, so when he asks for furniture deliveries I will just replace it with a blue or purple version! That way his house is pretty much the same, but imo looks better.

I generally just give them the bugs and fish, and when they put them out for display I just send them whatever furniture they replaced in the mail and usually they will switch back!

But you can definitely make up for skipping bug/fish/furniture errands by doing other errands above and beyond. Like when they ask for fruit, bring them perfect non native fruits, or try to write them a letter every day.

Yeah, I'd be interested in understanding this too. There is nothing worse than walking into a villager's house that is otherwise nice-looking and there is a nasty fish right in the middle ; o ;

Basically what everyone said is give them furniture that will go well with their house and fish/bugs that look good displayed.
And yes being really good friends with the villagers is one way to get their picture but the fastest way is on April Fools day.
But I prefer just building up friendships with villagers is much more accomplishing to get their pictures.

Letter spamming and repeated talking is the best. ALWAYS agree to catch the fish/insects, even if you don't do it, because agreeing will help. The biggest way to get pics and not mess up a house- perfect fruit. Give them a perfect version of what they ask for. Apple? Perfect apple! If they say any, give them a perfect that's NON NATIVE. It'll build up friendship fast.