test <- c("Testing $26,500\ntesting","Testing tesing $79+\n TOTAL: $79200","Testing $3880. Testing", "Testing -$69000Engine: $69000100%","Testing testing original price : $ 8 2 9 5 . Real price is $ 7 4 9 5")
test <- gsub("([$]|(?!^)\\G)[\\s,]*(\\d)", "\\1\\2", test, perl=T)
test <- gsub("^(?|[\\s\\S]*-[$](\\d+)|[\\s\\S]*[$](\\d+))[\\s\\S]*$", "\\1", test, perl=T)
test
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