Rick S is right, San Blas is a little out of the way and adds an hour to the trip but for us the great dog-friendly hotel is worth it. The hotel has large rooms, an on-site restaurant and a huge grassy area to walk our dog. There's a dog friendly hotel in Tepic but it's downtown - which in itself can add an hour getting in and out - and we're not sure we can get into the interior parking courtyard with our car-top storage carrier. You might also like to go a little further each day than we do but we like to be off the road by 3:00 and we also like to time it so we arrive at out destination around noon. We had a poor experience once with a rental on VRBO but by the time we arrived it was too late to start looking for an alternative. By arriving early we have time to look around if we have to and time to make a grocery/wine run.
Here are the hotels we've stayed at on various trips. I recommend you look at each hotel's website and also look at Trip Advisor and then make up your mind. All of these are dog friendly and have safe, secure parking;
Hermosillo Hotel Colonial Very nice, modern, large business hotel similar to a Red Lion
Guaymas Hotel Armida Same as above but getting old - what we call a faded beauty
Navajoa Holiday Inn As above, a nice hotel but the rooms are definitely showing their age
Los Mochis Hotel Ibis A new ultra-modern business hotel but the rooms are VERY small
Hotel Posada Los Olivos An older budget hotel but super cheap and for us, better than the Ibis
Mazitlan Mariana Beach Hotel and Apartments An absolute dump! We'd never stay here again. Going back we were able to book into the Hotel Aguamarina which we believe will be much better
San Blas Hotel Garza Canela A beautiful, large resort hotel - lovely grounds but the rooms are showing their age - another faded beauty
I hope this all helps
Cheers!