Get the 30year old boat with a rotton core, make that a 30yr old POWERBOAT, core does not have to be rotton to be affordable.
There are more of them to choose from and they give much better value re: living space vs marina costs and you won't be as tempted to spend money trying to fix it up. (ok a shot a powerboats but this is sailnet)
Don't worry about sailing, if you move into a small sailboat and try to keep one foot on land with a job and debts, sailing will be something to wish for, not something to do.
Sure some people go sailing everyday with their 35' liveaboard sailboat but the reality for most is much less sailing when living aboard. When you live aboard everything has to be on the boat, it takes longer to prep the boat to go sailing, sometimes longer than the sail itself and then you have to set everything back up when you return. Of course there are those that do that no problem with their Alberg but those working folks are a bit rare.
and it turns out if you talk a bit to those claiming to sail and liveaboard they often have houses, cars, property and many other land advantages. They are not really living aboard as much as sleeping aboard. Thats the way to do it but is pricey for some of us.
Ideally you want to keep your apartment and get a boat to use when you have time, that is if you are keen on getting into sailing. I'd suggest working with that. If you have parking, get a boat with a trailer, or a boat small enough that it does not have to be stored at the marina, or bit the bullet and go for both a place to live and a sailboat, it can be done.
If you are still keen on the liveaboard idea, say more than the sailing idea, the power boat will give you a very good taste of the liveaboard life and with min entrance and exit costs.
Then again if this is just a dream ignore this thread, and dream at least plan for it. That is often more fun than doing. Even I dream of sailing Florida or the PNW.....hey wait a minute, dreams can come true and it is worth the effort, go for it.