I really mean that. Welcome to the forum and more importantly welcome to a wonderfully fulfilling lifestyle. I get the tone of your post and I think you're very well placed to be cruising ready faster than most.
First I'll answer your question: about two years is the short answer. Three to five years to go offshore. Now with that comes a bunch of caveats. How much you sail, what friends you make, and how many books you read are the big factors.
I bought a 31ft wooden sloop, not knowing how to sail, and I hooked up with a good captain to race with and devoured every book I could from the library. I also lived aboard and thus was always talking with boat people and learned a lot from their experience. After that I took off on a 4 month trip up the inside passage of Vanouver island.
Was I ready? Ask anybody and the answer would be usually be HELL NO! But it depends on who you ask. EVERYONE I have ever talked to who has sailed for more than 6 months at a stretch has offered the same advice they all say "go and go now. If you stay at the dock you'll never leave."
I'm not advocating you go now, there's a little work to be done first but most people will tell you that you need to learn more, you need a better boat, and you need LOTS more gear before you can go. When you hear this take note of who the advice comes from. Are they still at the dock? Or do they have significant experience?
I suggest this:
SAIL as much as possible. If it means joining a club or buying a boat do it. Race, you will learn a great deal about sail trim and, in racing you will find yourself in situations that you would never voluntarily put yourself in (such as having a spinnaker up in 30kts of wind) but you have to get out of. There is much to be learned from racing.
Check out every single book on boating from the library and read as many as you can. You'll see many different opinions and you'll find where in the spectrum you sit.
Buy a couple books. "Chapman's piloting" and "the complete sailor" by David Seidman. If you learn what's in chapman's and follow it to the letter I can (as close as you can) guarantee that no harm will come to you. The complete sailor is the best book to teach the sailing part.
In your learning concentrate on two things above all else. STAY ONBOARD AND KEEP THE BOAT OFF THE ROCKS. The more you do to make sure these two things are looked after, the better off you'll be. The rest is gravy. This means being mindful and humble when on board and really LEARNING navigation and CURRENT.
I've probably already said too much but it's a start. If you stay coastal you can do it for 20K (marine swap meets are your friend) and you can do it soon. If you want to go offshore you are really looking at more like 40K.
PM me if you want me to rant further.
PS One last thing, the Coronado 25 is a fine boat that I've seen many time for just under $4,000. My parents learned to sail on one in SF bay...