Hi Shelley - your home buying process is similar whether retirement or not. You are on the right track with your prequalification. Your potential lender will need to look at what the income potential will be when determining your mortgage budget. Will this come from monthly draw downs from a retirement account, annuity etc. The big picture of how you will finance retirement even if the "new retirement" means still working and producing an income.
The potential to rent to own has its good and bad. Does not necessarily give you the strongest position in negotiations on price, since the seller is not getting out from under the home.
Coming from Arizona (I'm originally from the Mesa area though I have been an Oregonian for 30 years now)
it may not be a bad idea to get a short term rental as you determine your best location and finding suitable employment, and the new retirement budget.
If I can help further, please call or email 503-495-5231 / firstname.lastname@example.org