I just finished mine yesterday, so the memories are still fresh

. It all depends on your skill level and tool collection (or access to tools). If you follow FSM or Tim's superb videos, there is nothing hard about it.
But it is a LOT of wrench spinning, and you should always be prepared for some surprises which may require tools you may not have on hand. For instance my crankshaft timing gear was rusted onto the crank (unlike Tim's which popped right off), so I had to go round up some bolts to use with a harmonic balancer kit.
I had all the other special tools on hand (harmonic balancer kit, crankshaft holder, camshaft holder, seal puller, seal installation kit, belt tension gauge) as well as tons of hand tools and cordless tools and impacts.
It still took about two days (6-7 hours a day, given the early sunset), but I also wanted to degrease the motor and paint all sorts of brackets and pulleys, so you can do it much faster. But if this is your first time doing this, I'd set aside two full days just in case things go wrong. And have a back up parts chaser vehicle

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I've done timing belts on my Lexus GS which was much harder given its VVTi technology, so this was easy in comparison.
But don't be fooled, this is not for the faint of heart or a beginner (don't mean to offend anyone, I just don't know your skill level), so this would not be a good first project to get nice and intimate with the 5VZ internals.