Surrey is by far cheaper and has more lot area compared to Tri-Cities. Also, it is definitely longer travel time to get to Vancouver downtown if that is what is required of you to do. Having to travel to Surrey requires toll and now it is $3 to go past the toll bridge for every trip you make. I guess that is also why there is cheaper rent and houses there. I have many clients moving from Surrey/Langley towards the tri-cities area which is far more lively now with all the new developments. Watch for the new Evergreen line, Port Moody area and Coquitlam.
Many landlords will require a security that you will rent the place for the stated time and that security for you to be here in person, and a background / credit check. If you are new here, you might want to approach a rental property mangement and I do have the most reliable and less fuss realtor you can find. I can also assist you with this if required.
If you are looking for a hotel near Vancouver for your temp stay, please be prepared to pay for meals every day which will come up to be at least $60 for a small family as you cannot cook, you will need to eat out. I do have a basement suite near Coquitlam Centre that I can recommend and it is close to shopping mall and has a grocery store. The rent for a month is $995. Pm me if you want to know more.
Do let me know what kind of assistance you need.