好(不)容易 (with great difficulty)

"Finally managed it (with effort)"

• with great difficulty好不容易hǎo bù róng yì (= (idiomatic usage) with…好容易hǎo róng yì) = "with great difficulty / finally managed to".
• with great difficulty好不容易hǎo bù róng yìonly then / not until才cáito buy买mǎito / arrive到dào = "(I) finally managed to buy it."
• Oddly, with great difficulty好不容易hǎo bù róng yì and (idiomatic usage) with…好容易hǎo róng yì mean the same thing.

good好hǎo(not不bù)easy容易róng yì + only then / not until才cái + Verb

• with great difficulty好不容易hǎo bù róng yì stresses how hard-won the result was; only then / not until才cái underlines "only then".

I我wǒwith great difficulty好不容易hǎo bù róng yìonly then才cáimanaged to buy买到mǎi dào。

• with great difficulty好不容易hǎo bù róng yìonly then / not until才cáito buy买mǎito / arrive到dào = "(I) finally managed to buy it."

Recap

Read the full reference: HSK 5 grammar — Adverbs.