My question is about temporary/seasonal/surplus housing, and whether or not anyone here would have anything available that would be cost effective for the duration of each assignment..?

You will need to have some surplus funds for the unexpected.

If you are trying to get into the excess/surplus funds business, in GA mortgage holders have priority before the owners.

Other factors could be time of year and scarcity or surplus,

Our local government is sitting on about 10,000 properties in its surplus that they are auctioning off at really low prices.I am a chair of a local 501(c)(3) nonprofit organization in Indianapolis that is buying properties at low prices as part of the county's special nonprofit surplus property program.If anyone is looking to invest in Indianapolis, feel free to give me a call.

Tax deed surplus funds...

Mobile Home park managers or mobile home surplus stores will also be able to provide good recommendations as well. 

Live in one unit rent out the other and make extra principle payments with the surplus.

If @Eliott Elias is renting, but using his surplus savings to buy other investment properties, he's very likely to come out ahead versus simply owning his own home. 

The surplus goes to a repair escrow for now (eventual replumb/rewire) but I'm hoping to go solar within the next 5 years and increase the rents to include solar electric.