We have one from StudyBed which, whilst eye-wateringly expensive, has been one of the best furniture purchases I’ve made for our flat.
Our study/spare room is tiny. Only 4’11” wide and it was useless before we got it. We effectively used it as a cupboard. Now it’s used every day, and has been since I bought it in late 2018. It was my study for admin/campaigning work before lockdown but when lockdown came it was taken over by DH as my “work” isn’t full time or nearly as messy or noisy.
One thing that’s marvellous is that we can keep the bedding on/in it when it’s in desk mode. So I don’t have to find somewhere to store a duvet and pillows when its not a bed, as I would with a sofa bed.
I’m so evangelical about them that several friends have bought them and are very pleased. They, like I, love that the turn the spare room into a multi-functional space, and that you don’t have to clear the desk to turn it into a bed.
They do discounts if you’re introduced by someone who already has one - if you want one then feel free to PM me for an intro (I get a little cash back too).