>>1322451But he is asking for a specific Gravel bike and the least he should spend. He's not asking for a mountain bike that he can switch out tires on and is as cheap as he can get.
If I read him right he's asking for a, lets say, Trek Checkpoint ALR 4.
Quality Alu frame, 50c max tire, Full Tiagra compact groupset, hydro discs and a great frame for everything you want.
This will cost him €1500. It will last him a looong time and he will have fun with it.
Put €200 more and he can have 105 groupset.
Put €500 and he can have Carbon frame.
Canyon Alu frame Gravelbike also looks like a great choice.
Then again, people who WIN gravel races are running 28c slicks on road bikes because they are faster on the flat parts.