In my experience, anything older and European can be expected to cost money. Anything older and Japanese will cost something too, but if you buy right, the $ needed and frustration levels will be lower. I have had a ton of cars over 42 years and though I love European cars they have had the most issues and cost the most to run across Euro, Aussie and Japanese cars. I tend to run Japanese or the like for a while then indulge my Euro fetish for a while before retreating to something that is easier to live with again.
If absolute reliability is key and you're not handy with the tools as you say then I'd generally not be going for something that old, but especially European. Now I know people are going to jump on here and say "I have/had/know about an old (insert Euro brand here) and it's been flawless". But you'll also find plenty who won't.
I wouldn't say Snoopy is wrong, but he knows about Volvos and also knows all the independent repair guys so he's well ahead of the game in that respect.
If the S80 is the one I think it might be it looks like your budget runs to about 15k? Plenty of good reliable stuff for those $.