Rat left Outside

Question
My pet rat, LuLu, is about 9-10 months old. She likes to wander out on my patio while I am watching her. Last night she accidentally got left out. Luckily, she was there this morning, waiting as patiently as possible by the sliding glass door to come in.  I live in an apartment complex that has 'rodent hotels' with what I assume is poison in them. I seriously doubt she wandered that far, but how long would it take for her to show symptoms if she did ingest any of the 'food?'  She had a great appetite when I left for work, and seemed just fine, and glad to be back in her cage. Also, is there anyway to make 2 rats become friends that have been living together, but not 'together' for nearly a year? Thanks so much for your help!

Answer
Easy way to check if the 'hotels' have poison in them: it has to be listed on the outside of the box, usually on the front or side panel. It'll say "trap only" or "poison inside". Trap only indicates a glue trap, poison are the ones to be worried about. Either way, if Lulu had ingested poison, she'd already be a very sick [or very dead] rat, so I think you're just fine! They work very quickly and you'd be seeing symptoms already.

Regarding introducing your rats.. have they ever met before? If not, clean the cage very very well, move things around, give them a handful of treats in a neutral area and let them play with supervision for about an hour. Then set them up in their fresh, sterile cage and watch them closely. The rule of thumb with rats, as gnarly as it sounds, is no blood, no foul. If you don't see them trying to kill each other, don't separate them, let them work it out! If you hear screeching and hissing and even see some boxing or submissive/dominant behavior, that is entirely normal, and all part of the process. If someone is injured, remove them immediately obviously.

Good luck, and I hope Lulu continues to feel well!