My coils I usually run at 0.2-0.5 ohms and I vape id say 10-20ml a day. I chain vape a bunch, and I find that with all the vaping the wire gives within a day if I use high gauge wire (26+). I've switched to 22-24gauge and they seem to last a bit longer, I can dry burn and rewick. I think they usually give mostly due to heat fatigue (not sure if that is the correct word, because most of my coils at least, I know when they're bad because i can push on the coil itself slightly and the legs just break off. I usually just change them every day or two now because the flavor is just better with a fresh coil tbh and its cheap to replace coils if you build your own. If you don't feel like changing coils just make sure before you rewick it, run it under some hotwater then give it a good dry burn to burn all the residue that collects on the coils off, should taste a bit like a new coil after.
I wouldn't suggest trying to dry burn it while it is still wet. If that is what you are doing ( I may have misunderstood), then it is likely the reason that your coils are burning out so quickly. My coils last for several re-wicks, so about 1-2 weeks (I don't rewick unless vapor production drops significantly or if I want to try a new flavor by itself). I change them out if the heating becomes very uneven and I can't fix it easily. I build dual parallel coils at 0.2-0.3 total ohms with 24gauge kanthal. I also vape quite a bit each day, I couldn't put a number to it honestly, I don't keep that much track and my bottles aren't labeled with mL.
As far as the RDA itself wearing out: The only ways I have heard of them wearing out is if the insulator bushing on the positive post gets a short. They are pretty tough to find replacements for from what I understand.
Some other posters here are complaining about stripped screws... Have you guys tried checking out hardware stores? They usually have a sample set somewhere you can thread the old screw into to determine the size and threading, and then its just a matter of picking a length you like.
Hasn't happened to me personally yet that the screw has stripped, but I have stripped enough screws in my lifetime to have learned to 1.) use the proper size screwdriver, 2.) make sure the screwdriver is parallel with the screw, 3.) apply more pressure the harder you are trying to twist, and 4.) don't overtighten screws.
Hope you enjoy your RDA! Learn to build coils yourself and don't waste money having someone else do it! If you ask at my local shop they will just teach you how on the spot.
Oh and don't overpay for wire! One shop near me sells it for $1.00 a foot, and another sells it for about $0.35 a foot!
If you're not enjoying smoking from a RDA due to coughing (throat hit, etc.) be sure that you are using very low nicotine (I use 2 and suggest you don't go above 4... ever), and try higher VG ratio mixes for smoother hits. I personally vape nearly 100% VG and enjoy it much more than PG mixes. I haven't had noticed reduced flavor at all!
Happy vaping
