Ya, doin great Pyro!
You could make a pretty cheap hoop house out of Gray plastic Conduit, rebar stakes, and plastic sheeting. Jorge Cervantes has a couple examples of those in some of his videos, outdoor growers in Cali using them.
Make your frame a little shorter than your fence, that way you have the option to turn into a dark room if you need to ever force flowering on some photo's. Use the Plastic GRAY pvc pipe, since it won't chemically react with the plastic like the white pvc does( the chemical reaction prematurely deteriorates it). You can even put something like the green snow fence looking mesh along the sides to give a visual block, or put some shade cloth over the frame if they get to hot this summer.
Can't say if it would keep the critters out, depends on how tight the bottom edge is I guess, and how hard said aminals are willing to work. You could run some chicken wire up the sides perhaps. It is possible to put a heater in there at night, if you are smart about it and use good judgment. You can run into humidity and ventilation issues, mainly if plants are flowering inside, but if it's just to give some early season protection, should be fine in vedge/ very early flowering.
Might not fit all the needs, but an idea at least! There's maybe a little bit of useful info on my thread: Sitting on some Organic fertilizer.