The breeder has a lot to do with introducing them to the pee pad. My baby Izzy knew her pee pads pretty well when I got her and actually hits it better than her older sister who is 1 yr 9 months.
Zoey started holding herself all night by 4 months so she ended up in my bed. When I feel her get restless inthe night I would take her down stsirs to her pee pads so she could go. To this day she gets up in the night and goes down to pee on the pads, by herself now...She just doesn't always hit the pad. Which is very aggravating....and yes my two both go on either pads. I put a paper one beside Zoeys cloth one and I see they have no preferance .
Frustrating thing now is if they are so distracted by each other if they have to go ....they just " go" wherever.....if they are not distracted with each other they hunt down the proper area. Little fur butts know better too.

Oh talking about bells...that is so worth doing. Zoey my oldest is my summer pup and I bell trained her to ask to go out. Which she did very well...when we were outside she would go then...But winter came so it was pee pads and she got away from the bell . Recently she discovered her bell again. Well it's cold in indiana but I let her out! She didn't pee but she still tries to con me to let her out.
Now Izzy is my winter pup , she's pretty well pee pad trained so it's too cold to bell train her now. We'll see how it goes when it warms up.

Max was 100% reliable with pads. Teddy was 8 months old and 100% outdoor trained by the breeder when we brought him home. I re-trained him to pads. Peeing was no problem, but pooping took 2 weeks of coaxing.

Strangely, Max guarded his pad, so we had to put a second one down to designate as Teddy's. That didn't last very long.

Yes, Max guarded his piddle pad, but not food or toys. :D

I know that feeling. It's a big part of the reason we got Clark. Maple was just absolutely obsessed with my parent's maltese mix, and LOVED him a little bit too much (She scared him away, lol, even though he's twice her size). I was concerned because she was already older (she'll be 2 in March) and does pretty well on her own, but when I had my parent's dog for 2 weeks and he left, she looked very depressed. She loved having him around.

So we decided to get a puppy for her. Not just for her, obviously, as I have 4 kids and they would fight over Maple constantly, who got to take her for walks, who got to have her at night, who got to bathe her etc. We all needed Clark, lol.

Maple and Clark get along great. He's pretty aggressive as far as puppies go, but Maple seems to know how to control him, even though he's gaining on her in the size department.

Maple was never very well potty trained, but once we got Clark and he was pretty well paper trained, Maple has only ever had accidents on the paper ever since (And she's actually gotten better going outdoors, I think she's disgusted with Clark now, LOL). She was also very maternal with him, if he cries (which he does often if he doesn't get his way, he's very vocal) she will come running to help him and try to comfort him. It's very cute.

So even if you aren't ready right this minute, I think up until a dog is 2 they will still be pretty accepting. After that they can get a little set in their ways. My parent's dog is 5 and absolutely did not like Maple or Clark (We are over there a lot). So there is some time yet.

Good luck with your decision!

Lol! Oh that's so funny! Is Max still like that?

No, thank goodness! :D He gave up after a couple weeks and started sharing pads.