I don't know where you are -but I presume the US? It sounds like most of your equipment will have to be scratch built -I use 16mm (1:19.1) scale which is not far off 15mm (1:20.3) scale. This would give you a 3 feet gauge track to work from using Gauge 1 or a near std gauge if using Gauge 3...
Battery power I have to agree with as all but two of my locos use them, (the others burn Butane gas).
One thing you will have to look out for is a good knowledge of the soil and what is underneath it in your location, allied with the weather...
Have a look around the "Home Page" -feel free to steal, crib, or grab any of the information there.
regards
ralph
The Home of Articulated Ugliness
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