Sleeping arrangements for 1 year old and 3 year old? Bunkbeds?

[DitaVonCheese]

Evening. We have a 1 year old (but large) DS and a nearly 4 year old DD. DS currently cosleeps with us. DD sleeps in a toddler bed in her own small bedroom. We have a third larger bedroom which is full of crap the spare room.

I would quite like to start moving DS out to his own bed in the next few months but can't work out the logistics. I think the options are:

(1) move DD to bigger room in single bed, move DS into her small room and toddler bed

(2) move them both to double mattress in larger room (think they might like this as they are very close/cuddly and also both used to cosleeping?)

(3) bunkbeds?!

(4) slightly lower bunkbeds as per Ikea Kura bed, maybe with toddler bed underneath or turned into bunkbed as per this hack?

Is DD too young for a bunkbed? She currently has just a foam bumper along the side of her bed and doesn't fall out and I think my Dniece was in a Kura last year and is 7 months younger than DD ...

Or is there some other solution I haven't thought of? Two single beds? Feels like it would take up a lot of space.

Bunks are for older, I thought about 7?

Can't they just have two normal beds in one room? Can't take up much more room than a double mattress.

Our twins were 3 when they went in a bunk bed. The top bunk was safer than the bottom as it had a really good safety rail. As long as you don't exceed the maximum matress depth thy can be fine. If your 3yo can get up and down the ladder safely it would be okay.
OR buy a bunk bed that can start as 2 singles..when they are older you could make them into bunk beds to give them more floor-space.

Our dses (2yr 10mth age gap) were similar age when we put them in to separated bunk beds. Had them as two beds for about 18mo then made the bunk beds when ds1 was 5 and a half ish and could go on top bunk. They're still in them (nearly 9& 11 and a half)

My dd had a cabin bed age 3 and was in a bunk bed age 4 and we've never had a problem. DS moved into a high sleeper (bloody impossible tiny box room) at 4 and has never had a problem either.