You have already had a lot of replies and good advice, but I'll add anyway
We have two lab mixes, Sadie, we got when she was 8 weeks, and Cincy when she was 6 weeks.

With Sadie, Ralph was home the first week. When he went back to work, she was crated from about 7:45am-4:15pm. It took her til she was 4 months til she could reliably make it all day without messing. Sadie is no longer crated. (She is now 20 mos.)

Cincy was in her crate from the beginning. For the first few weeks, Ralph would come home at lunch and let her out. most days that was enough for no crate messes. She was realibly making it all day by the time she was 2 1/2 or 3 mos. Cincy is still crated during the day, most days ( we are slowly trying to get her her freedom!) but not at night.

My parents have three dogs. Oreo, the oldest, we got as a puppy and she was trained almost immediatly. She was let out at lunch and then when we got home from school at 3. Dazzi, they got when she was 1 1/2 and she was almost housebroken. I don't think they ever had any issues with her having accidents at all. They recently got a puppy who is now 4 months old. They are home everyday at lunch, yet he still seems to have accidents in the afternoon in his crate.

Every dog is going to be different and even a housebroken dog may have some adjustment issues. But with traiing and patience, any dog can be house broken, even an older dog who wasn't previuosly.

Good luck !!!