Not always I bought a bucket truck from a dealer in Oregon who got it at a auction in ca it was an ex Sacramento Dpw truck it was a forestry truck they didn't use it for tree work. This April I'll own it for six years besides routine oil and filters I've put in a set of batteries and tires last...
Here's a good truck that you can make a great tree truck without going in debt. It's on eBay now bids up to 6k. It's in FL You can call them and ask for price say you pay 10k good truck and engine no emissions bs easy to work on good boom I have one 55' sand blast paint and build head ache rack...
I started off with one with 6 cylinder gas no auto feed made a lot of money with that chipper never let me down never had one issue with it and I bought it used from dealer.
Most guys I know have diamond plate truck fuel tanks and they take a beating in the back of the trucks. My chipper has diamond plate fenders, tool, battery boxes so a a fuel tank wouldn't look to bad.
I'd bring an extra or two of fuel cans that's a lot for a bigger fuel tank. You have martins welding in pa they can fabricate you a nice aluminum for a lot less I bet.