[Peter B - CV8]

If your valuation comes in at $250k - then most lenders will loan up to $200k (ie 80% of it's value) - without Mortgage Insurance. Obviously you also need to show serviceability.
So you could refinance ($150k) + include your car loan ($33k) + total new loan of $183k.
If the valuation comes in lower than say $230k - which it very well might, due to the current work in progress on the property, your stuck. This is why someone (no doubt with a bit of loan/valuation knowledge) has suggested you should try & finish the house reno's first - so it looks nice & has the best chance of valuing up without any dramas.
You mentioned that you don't like people, paperwork & have already burnt your bridges with one Mortgage Broker already. You're going to have to change your attitude in the current lending climate where lenders are focused on living expenses & are making customers/Brokers jump through hoops to get a loan approval...
Check with your car finance mob about any early repayment penalties as you might be up for an extra couple of grand there as well.