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Eliminate repeaters that are currently in existance as batterries will eventually go dead. What band is going to be best?

Not necessarily. While some don't have good battery backup (for example, in NJ Cherryville has a MASSIVE battery bank) many ham radio repeaters are based in emergency ops centers which have good backup power.

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What radio manufacturer seems to make the best equipment?

I like Kenwood the most. That's just me.
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Are there models that are fairly portable that cover more than one band, or is a seperate unit required for each band?

There are many, many multi-band radios, from handheld to in-vehicle.

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Since someone will eventually setup a repeater in the aftermath what would the most likely choice of bands be?

2Meter (144 Mhz)
440 Mhz
Possibly 6 meter (50 Mhz)
HF bands of various flavors.

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What band in the most portabel size unit allows for the longest distance communictions?

A portable AM SSB High Frequency portable will really get out.

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I have noticed that marine band radios usually have higher wattage output, is this a fair alternative?


Not really, that's a 160 Mhz, similar enough to 2M ham...