I'll preface this by saying I'm totally over thinking it.

We are starting to think about transiting LO2 out of the crib. Currently, we live in a 3 bedroom apartment. We will be here at maximum 4 more years. This apartment is likely the largest place we will live in for the foreseeable future. When we move, the kids will most likely have smaller bedrooms or might even have to share a room. Of course, you can't foresee every situation but I would like the bed to last until LO leaves home. We have overnight guests maybe 5-6 times per year, but they stay anywhere from 3 nights to 2 weeks. We have one sofa bed for guests.

For simplicity's sake, let's say the beds are all roughly within the same price range.

Bed 1: twin, same model as LO1's bed (it's slightly narrower than a normal twin but over 6 ft long). Low to the ground with no possibility of storage or trundle bed under it. I'll add that I'm really in love with the style of this bed.

Bed 2: twin with a trundle option for occasional guests (in addition to the sofa bed).

Bed 3: full size bed (giving the full to LO1 and the old twin to LO2). We could potentially have a visiting couple sleep in the full, put their kids on the sofa bed and have LO1 sleep on the couch, or some configuration like that. But a full may not fit in a future smaller or shared bedroom.