Is there some secret to keeping Corgi's derrieres poop-free? There, I said it!

We are new to Corgis (via taking in my Mom's) and I don't know how to solve this.

Since we don't know what she has been eating (my Mom had her and has dementia so I know, due to how huge she is that she fed her anything and everything).  We are experimenting with weight-loss dry food formulas and though her BM's aren't  particularly messy, she does seem to leave some behind and I have to be sure she is clean (ick) before she comes in the house or clambers back in the car after a walk where she has done her business. 

Do folks take their dogs and ask groomers to trim that area? I have tried myself but she sits down every time and I am afraid to snip her instead of her fur.  Is this an odd question?

Do others have the same issue... I feel awkward asking, but want to do the right thing. Is it OK to cut a bigger, barer patch in that area of her anatomy?  Never had a dog without a tail!

I know know why my Mom's house had stains all over it and do not want the same here. Plus, it makes her stinky!  Poor thing...

I appreciate any feedback or tips -- maybe I am the only one out here with this issue but if not, please chime in. I hope I am not offending anyone by asking.

Thanks,

Valerie (and Duchess)