Diddy‘s house is underwhelming when you walk in and defintely not worth $60 million … this according to the investor who says he’s offering half the asking price.

We caught up with Bo Belmont — founder and owner of real estate company Belwood Investments — out in Los Angeles Friday … and, we had to ask him about putting in a $30 million offer for the rapper’s Holmby Hills mansion.

First off, Belmont says this is a real offer … telling us his company has emailed the listing agent for the property — though they haven’t heard back yet.

As for whether Diddy will accept an offer so much lower than his asking … Bo says he might — after all, his company was able to purchase Kanye West‘s gutted Malibu mansion for nearly $40 million less than Ye originally wanted.

Bo plans to stick to his guns in any negotiation with Diddy, he tells us … ’cause if Diddy wants more and comes back with a counter, his plan is to offer $27.5 million — taking money off the table instead of piling more on it.

Worth noting … Bo’s fine with all of the alleged activities that may have gone down in the house — explaining he plans to completely redesign the interior so it looks and feels nothing like the current mansion.

We’ve spoken to other realtors in the past about Diddy’s mansion BTW … and, they say two of the big issues with selling the property are the asking price and the stigma — so sounds like Belmont’s keeping both in mind.