Newbie Question:Advice on used AllWeather TC for work travel

I researched some very nice used Bigfoot and Northern Lite TC for possible choices. They all were less then $15k and in the 98-2004 model years. A Wabasto diesel heater is about $3200. A Wallas cooktop is about $700, add another $1000 if you want an oven too. Cummins makes a nice diesel gen set for RV use that could be installed in the old propane locker. They're about $5700. So if you're really wanting to go all diesel it can be done reasonablly if you find the right TC to build on.