Gosh, where to start...
We take kids, all ages. Partly because we have twin sons (the ds5x2). So when we were planning our B&B, we figured romantic getaway was not our niche.
We get quite a few kids, especially traveling in the summer. We recommend them to take the third floor room with the futon (and room for a fold out bed), and they love it up there. We have also put the fold out bed in the first floor room. We have four rooms and none of them share walls (well, the two on the second floor have adjacent bathrooms) so sound proofing is not a big issue. [Kids have also stayed in our room with two twin beds.]
We make it quite clear on our website that we have kids, and sometimes I even do a verbal disclaimer when taking a reservation on the phone. If the presence of children is a problem, then people can self select to stay at one of the other B&B's in town (all lovely, none take kids). Ironically, we get a lot of people who come anyway, including honeymoon night stays and getaway couples... other amenities of ours win them, I guess. And many, many guests have said, "Not my kids, not my problem!" (It helps that mine are cute, and well-behaved... people enjoy them a lot.) But I, too, when in public, am less bothered by other kids than my own's behavior!
I do offer other guests in the house to eat separately from the family if they prefer... in their room, on the patio, different time... but so far they've said, no, they'd prefer to eat with the family.
We have two high chairs, two booster seats, a diaper bucket, and a pack and play. We also have baby gates. (For that matter, we have shower chairs, bath tub rails and items for the more elderly crowd as well!) We do no child proofing beyond giving the baby a plastic cup for breakfast.
As a mom who traveled with kids, I would take a B&B over a hotel any day. When they were babies I hated staying in hotels... the only interesting thing in the room was the toilet paper, and there was nothing on TV. At a B&B they can go to the back yard, or watch a video, or simply feel more at home. When they were babies I wasn't getting in the pool with them. And when we travel now, we generally travel with a purpose (wedding, etc.) so we're not hanging around the hotel pool. All that to say that a hotel pool is fine if you're spending a lot of time at the hotel (like on vacation at a resort) but most of our guests with children have been here briefly then on to their wedding/ reunion/ other activity.
The excuse "our inn is not child proofed" always makes me laugh. It means to me... we don't want kids here (which is fine...). Child proofing only applies to babies who put things in their mouths or fingers in electrical outlets, or fall down stairs, generally 2 and under. At that age the moms have to watch them like a hawk anyway. After 3 or so, none of that matters anymore.
Most of the kids who have stayed here have been well behaved and fine. It helps that our boys take them in hand, or take them out to the back yard to play. The ones we had recently were the worst so far, and only because one was a bit noisy... when she was here, which was rarely. One of the other guests said the next morning, "I heard your kids last night, but they didn't bother me at all." Not my kids! We weren't even home!
And I've read comments about how can the parents relax when they take their kids to a B&B? ... always having to watch that the kids aren't touching, breaking, yelling, etc. Well, that's our (we mom's) reality wherever we go. This same family, when departing, expressed how grateful they were for the relaxing time. This from the mom who spent her entire stay chasing with the baby and shushing the preschooler. It WAS relaxing compared to being at home! She didn't have to cook or clean!
All that to say that taking kids is a viable niche, and there's definitely a market. I even had a mom who said, "I can't wait to tell my husband where we're going to stay!"
As far as policies, and handling of kids... well, being a mom is a useful thing. As you mentioned, other parents don't like people interfering with their children. On the other hand... your house, you're the boss. The mommy voice (as well as the mommy look) goes a LONG way, and I'm not afraid to use it (actually, I've used it on adults...). If you are respectful to the parents, but also firm with your boundaries, it can be fine.
Our policies re children state:
Children: We love children, and our twin sons (age 5-1/2) will be happy to welcome yours! Let us know the ages of your children when making your reservation and we will make every effort to accommodate them and you in comfort. Please be considerate of other guests and help your children to behave appropriately in a bed and breakfast environment. Also, please do not leave your children unsupervised at any time.
We charge an extra person charge of $25 per night for anyone over 10. I waive it sometimes... but not if someone asks me to!! (Learned that one the hard way...) Mostly the charge covers the hassle of setting up the extra bed and taking it back down again.
We make towel elephants (like they do on the cruise lines) and put them on the extra bed. Sometimes the kid is older (last night's was a 17 year old girl) but we do it anyway... it's fun even if they're too cool to admit it.
So, don't be afraid of the niche... it can be a very good one. I'll clean kid mess over pet mess any day, while plenty of other innkeepers are the other way around. To each his own! We have kids, we like kids, we take kids, and we haven't regretted it so far.
=)
Kk..