Betsy,
In the case that you have not figured out that this is actually a hard question to answer, let me try to provide some guidance that may help you decide.
Laser printers are cheaper to run and have more "sense of humor" for long idle times. They require significant AC power to run. They could care less about temperature of storage or operation. It has been my experience that some do not like to be transported in rough riding vehicles. This makes them get all messed up and they don't like this.
Ink jet printers can be run on very little power (but most do require AC). The ink cartridges are as expensive as the toner for most lasers. They also do not like to be ignored for long periods and even less so in hot places/times. If you are looking at ink jet, get one that has the print heads in the cartridge, the when a print head clogs, you can change out a cartridge.
My home office (the business is now closed, but I still have the printers) has a networked color laser that is fast and does a wonderful job (even being 15yo now), but it is heavy and a power hog. The coach was a mobile office for some of its life and I still carry the scanner/copier/printer that is now way over age also. But I carry the cables in the paper feed and the spare cartridges in the outfall tray. I can and have run it on a 60 watt inverter (it is actually about 30 watts). It is so light that I can put it in a top locker.
Paper is the hard thing to carry. Either get a plastic box the right size or hope a friend can provide a smaller than ream stationery box. Remember to pack a few envelopes and some photo paper if you get a color printer.
I hope this is some help.
Matt
Matt & Mary Colie
A sailor, his bride and their black dogs (one dear dog is waiting for us at the bridge) going to see some dry places that have Geocaches in a coach made the year we married.