I have been modelling railways for about 40 years or so, being interested in the Midland Railway and also Colorado narrow gauge of the 1880's with a liking for the Denver South Park & Pacific RR, which used Mason Bogies, or single Fairlies,.and I have built one of these.
I am now retired, after being a policeman, and having moved to my mother in laws house (to look after her, when her husband died) I had a large garden, that was reduced by some building work, (workshop for me included), I still had enough space for a G scale garden layout. Not enough for the Midland, but OK for US narrow gauge!
A loop was built around one lawn with a station (depot) at the back of that lawn, at the end of it was started a small village built by me, and it is still being added to. A new railroad extension is under way round the other lawn now.
Meanwhile I build the rest of the railroad, locos etc, as they are not generally available at a reasonable (and affordable) price. That keeps me busy - with a huge 'to do' list, that gets longer by the day there is plenty to do.