I cannot recommend a particular brand - but if space is an issue, I would go for a sit down machine.
If you are set on a longarm - look at the various frames. Some of them will allow you to expand or contract the length. Not an easy process, but assuming it takes you 6 months to assemble a Full/Queen quilt top.
I just bought a LA -- and have to say that learning to use it has been a much harder learning curve than expected. Also - I no longer have a formal dining room, but some sacrifices were to be expected....