Smokers' clothes and hair smell strongly of cigarette smoke. Their cars do too. Their teeth are often stained yellow. They spend money on cigarettes that would be better spent on other things. Their need for a cigarette often arises at inconvenient times.
Smokers are at greater risk of significant medical problems than non-smokers.
The first three premises are largely acceptable by common knowledge, though the word 'strongly' is perhaps unacceptably vague. The phrase 'inconvenient times' is also vague, but perhaps not unacceptably so. It is common knowledge that smokers are at greater risk for medical problems than non-smokers, so that premise is acceptable. The premises all seem to be relevant to the conclusion. They are the kinds of things that some non-smokers might care about in finding people attractive or unattractive.