"property that can't appreciate"

[Eric Calabrese]

Hey everyone, I'm in my first contract  in the due diligence period and after walking the property and thinking of renting as is for how many years i told the agent if i get the house I'd like to renovate it before i sell to max it's potential. He then tried to tell me that no matter how great i make the house look i won't make a profit off of it during the sale because it's a good rental area but will only appreciate 3%. Every real estate investing book I've read has always told me that putting in money will increase your return. Is this possible or is the agent just incorrect?