If you own the condo, why did you not get a HELOC to use to pay for the remodeling? I would think if you can get a car loan at 3% you would be able to get a HELOC with a similar rate, which would mean you wouldn't need credit cards at all.
If you are able to vary the time of your 401(k) contributions, why not pay off the CC first and put in 401(k) money later? Or are self-employed people able to put in 401(k) PY contributions through April 15th the way that others can do for IRAs, and you are deciding whether to make a 2016 contribution?
I think, if you have a shortage of cash for getting 401(k) contributions and CC payoff done all in 2016, it might still make sense to get a HELOC, use it to pay off the CC ASAP, and then use your earmarked funds for 401(k) contributions.
Edit: Just before I posted, I saw robartsd's post. A transfer to a 0% card would make sense, too.