Oh jeez, another one of "these" protagonists...
-gullible idiot
-no common sense (shows his big bag of money around like an idiot)
-too soft/forgiving minded (just beats unconscious those who attempt to murder/rob/sell him into slavery)
-naive (trusts random person who he just met, if they just happen to be a girl/cute)
Those alone are just a huge turnoff as a reader, but even among those, he has also one of the biggest flaws there is.. Stupidity (basically comes along w/ the other listed traits... That whole scene w/ the bandits, and the girls spoken words after it.. "Hmm what does she mean by that".. xD Ugh what a joke.. (this authors writing I mean that is)
Also, clearly his mother was an idiot also, since she didn't teach him anything regarding worth of money, and how to become an adventurer, and how NOT to trust strangers, etc..
This seems like a very poorly thought "copy of a copy" type of an isekai.. Which is a shame, since that setting can be an excellent start for a story, if you have the brains to create something a bit more original.