Before I bought Ocean Child, everyone told me that yachts are expensive, both in money and time. But I didn't realise how expensive.
Ocean Child was built in 1995, so she's now more than 20 years old. Old boats need a lot of work to keep them serviceable. And money... so it's better to spend more initially to buy a boat in good condition, and a boat "fit for purpose". If you hope to cruise oceans rather than coasts, my recommendation is to buy a boat already fitted out for ocean cruising. There is actually a LOT of difference between an ocean cruiser and a coastal cruiser. So be careful when you buy, and be prepared to spend over your initial budget.
As for steel boats, it's worth noting that steel boats generally rust from the inside not the outside. If sacrificial anodes are maintained, along with a good paint coating on the hull, there will be little rust on the outside of the boat. The inside is entirely another matter, where rust will be driven by condensation water, along with small salt-water leaks from fittings such as portholes or the anchor locker. If you buy an old steel boat, you must inspect the boat's inner hull, especially areas where water can collect and sit un-noticed.
It's not practical to get tradesmen to cover all maintenance on a cruising yacht. There is simply too much of it. You must do a lot of it yourself, and this is where an enthusiastic partner can be a big help.
Since I bought Ocean Child, I've spent about seven weeks on maintenance for every week I've spent sailing. My best year so far has been 2015. During that year, I spent 41 weeks living on the boat, and of that time I spent 12 weeks cruising. That's not so bad, a ratio of roughly 1:4. If you talk with other cruising sailors, I think you'll find my experience is typical for older boats.
As for 2016, it's now the beginning of April, and I've spent 2 weeks sailing out of three months on the boat. Most of the rest of the time has been spent on boat maintenance. But sailors are always optimistic, and I haven't planned any major maintenance stops for the rest of this year! Of course this work will catch up with me, but I hope not until I've left Tonga and reached Vuda Marina in Fiji.