A former close colleague from work emailled me last night to ask me to photograph her daughter's wedding next year.
I'm not going to do it because I don't have the equipment, insurance or any experience with any sort of photography that involves directing other people.

This is not an attempt on their part to save money. The daughter is the last of her peers to get married, and she hasn't liked the look of any of her friends' wedding pictures, which effectively rules out any of the togs within at least a 25 mile radius.
She isn't really the sort of young woman who would like a formal or 'fashion' style and that's all that I can find on a quick Google of photographers in the nearest city. I'm sure she wants more of a 'snapshot' look, not because it's currently fashionable, but because that's the sort of girl she is.  But even I know that getting a 'snapshot' look is like Dolly Parton's comment, "It takes a lot of money for me to look this cheap!"

As I can't make any direct recommendation as to a photographer to look at, what sort of things can I advise her on while finding someone to meet her needs? Obviously, I'll advise on double checking to make sure the tog isn't using stock images. I have no idea how to check if the tog has used models for their portfolio. This could be important, because another thing the mother often mentioned to me after weddings (as I was the 'person interested in photography' I got all the 'wedding photographer stories' at work) was the amount of time the tog spent taking the photos, which of course drives the guests nuts, especially those who don't know anyone else there. So if they've only used models, maybe they'd take hours getting everything perfect.

NB, this isn't a request for bids. Although they weren't asking me to save a few bob, they're also not in the market for jetting in a photographer. I want to be able to give some postive advice when I email them back with my declining of the job.

Make sure you friend meets the prospective photographer sees 'whole wedding' images ideally in print form - and several weddings to gauge consistency. Any websites that show bride and groom without bouquet, bridesmaids or any other guests are a dead giveaway they were two models posing for a wedding dress shop...

Buy a bunch of disposable cameras and leave them on the tables. Let the guests randomly take photos (give them to kids).

Yup, I had thought last night of suggesting this, but it had slipped. Tx for the reminder.
H*ck, it's at least 15 years since I've even been to a wedding!