We are generally strongly against paying for services like this. This is a broker.
In general, we strongly discourage you from using brokers for fundraising. Brokers send a strong red flag to most VC's -- it's worse to get connected from a broker than to be introduced neutrally. And so, if this team is perceived as a broker by investors, that's generally a bad thing. Why? Because most VC's perceive brokers as being compensated / rewarded by completing fundraises -- so they know their interests are not aligned, and it makes them skeptical. They also will question the quality of companies going through brokers b/c the assumption is that the companies could not raise on their own.
It's best if he invests and you can give him some additional equity -- usually a 10% kicker on what he invests in you -- for his strategic help. So if he puts in $100k at a $30m cap say and buys .03 percent, you would give him an additional 0.003 percent.
If you do think he's worth exploring further, make sure to ask to be connected to 3 founders he's worked with to chat with them -- ideally also ones that did not raise capital to get their perspective.
Also, he should not be charging the $125K upfront. 4.5% is fine as a success fee if you want to use a broker, but that's only upon completing the raise. And you should get clear what they earn the 4.5% against -- are they just introducing you in or doing more? Most VC's really hate the fact that 5% of their money invested into the company immediately gets taken out by the broker.
I'd see if he wants to invest at a discounted rate and ideally he'd get some equity sweeteners for connecting you into investors that invest but not cash.