that will open/close the blinds depending on how bright the outside is
(with the ability to remotely change as needed),
and stay closed at night.
Having made from scratch a photocell-controlled light using a Schmitt trigger circuit with two BJTs I must say your project is ambitious.
Having seen motorized heavy duty shutters in Germany I have some idea of the power it takes to do this. The wall transformer was fist sized, ~25 cubic inches.
I think the optimum solution would be a photocell along with a programmed timer that knows when the sun sets and rises (this info is available from the Naval Observatory) and it changes with your latitude and the season. You also need to sense when the blinds are fully closed and fully open which means limit switches or motor-current-sensing circuitry.
This will be a combination of analog and digital circuitry.
The parts cost might be up to $50. Interfacing to an existing product might be more difficult than starting from scratch.
If you have any other design constraints (Bells and Whistles) now is the time to post them.
Now I can add one more to my name meaning list
"Linda (name) The name might be derived from the same root as the linden tree, from Germanic lind meaning "soft, tender" ultimately from a Celtic root. The image of the tree is used to indicate a gentle personality."