Over the years I have gotten the occasional crack about trains being a rich man's hobby. I have had many blessings bestowed upon me, but wealth is not one of them. All a hobbyist needs is one train set to create even the largest layout. One thing that is required for the large layout is the real estate, not a lot of trains. You need a space like a large basement where you can spread out your stuff. For me the basement would be storage space otherwise since it usually doesn't have heat and can get quite cold in late winter. Now with the high cost of energy, most people would be unable to afford to heat a large space like a basement if it is not being used as living space. (I will divert heated air from a spare bedroom into the basement layout space a few hours before an operating or work session, or when sharing the layout with guests. Safe use of an electric heater also helps to warm the space only when needed. Always keep humidity down.)
So, the solution is simple: A small layout in a small space! Believe me, you can have as much fun with a small layout. I didn't believe it until I had finished my large layout. Yes it is nice to realize your dreams about seeing your train travel over a long distance, but once you have done it, the magic fades. I enjoy small temporary layouts as much, even more at times, since I can do something new every time. The secret is in being content with what you have!