Your file will be transferred to your local office only if the Imm. officer working on your file is not satisfied that your relationship is a genuine one(it was entered to acquire PR status) or if there's some inadmissibility involved(i.e. criminal records) and it needs further assessment.
If the immigration officer doesn't have any concern about your file, then it will be all processed in Vegreville and then sent to your local office for finalization, i.e. landing interview, and for others minor checks.
Also, for INLAND applications the medical may be extended for 1 more year, making it valid for two years. Be careful because there're a couple of things that are different from OUTLAND processing.
Your OWP will only be issued once you have reached and have been approved first stage of approval, which is taking 9-10 months lately.
I don't know regarding the payment for rehab, but all payments for Sponsorship + open work permit can be done all through CIC website and if you do all the payments together they will be printed on the same receipt.
