I would use all 3 plus look at properties currently available for rent that are similar to what you are trying to comp (3 bedrooms/2 baths; similar condition; size; etc). 

Another thing to consider, most single family bedrooms rent for 800-1200 monthly depending on the area.

Renting by the room doesn't make sense for a lot of people but when you have 4 bedrooms and 4 parking spots it might. 

Found the rules: 3 bedroom or less, 600 feet from other strs, 2500 feet from hotels.

And the long term is going to be really solid.Right now, the 1 bedroom 850 to 1,000 sq ft cabins are the sweet spot. 

On the house hack, you can divide common expenses by square footage or bedrooms, whichever is more advantageous. 

I want to replace it with a small 2 bedroom 800 sq ft house.

If it says on the website they pay $1,500 for X number of bedrooms, they probably pay closer to $1,150 once they account for the utilities.

Also, I'd lease out the other bedrooms for additional income as well as practice screening, leasing, and interpersonal comms.  

These are the pros and cons of these markets as I see it: Riverside: Larger units with more bedrooms; I can afford better neighborhood with less crime (50 percentile); properties are less old but ugly.