What to use if I just want one cleaning fluid?

Of the two over-the-counter brands I've tried (RRL/Mofi, AIVS) I'd choose AIVS.

RRL/Mofi Super Vinyl Wash leaves behind a lubricant which makes surfaces very quiet, but it also limits HF extension and dynamics. AIVS doesn't, and it contains more cleaning agents so it's more likely to remove whatever's on any particular record.

IME no single step or single step + rinse method is as effective as multiple steps. Different contaminants often respond to different cleaning solutions. But if one solution is what you're willing to do I'd choose AIVS's One Step.

groovy cleaner...sold in used record stores almost everywhere

Art du Son.

Thanks everybody. To Rgordonpf, I have maybe about only 200 records right now, but with the seeming growth in the last few years of 180 and 200 gram, and 45RPM releases I have started to occasionally buy some new disks, so I guess it may get a bit larger now.

Doug, I will not argue the probable superiority of a multi-step method, but like Gibson58 I just don't have a mindset to do that kind of thing.

Do try the Disk doctor, I use that. I have used a few out there and disk doctor seems to work the best.