Tips to finish Russia Level 1 in Gold Time?

I have tried this level several times & just cannot get it completed in gold time. What am I doing wrong? Part way thru the level they want you to soup up 3 Horses. However, by that time I don't even have enough money to have finished upgrading all my buildings. And the Horses that do come along are too expensive ($540,000 - while I have less than $100,000). Usually by the time it gets down to 2 minutes left I am only finishing the first Horse. Please help!

Fix the 2 broken cars you have and sell them.
Buy any cheap working car you can and sell them right away again. Don't bother with broken ones or upgrading them. Wise always works good (130k worth, buying for 104k, selling for 156k).
Upgrade your mod and paint station when you can - be sure to have around 300k left, you'll need it to buy your first Horse and you want it as early as possible.

Once your first Horse is completely upgraded / insured / waxed, it's rental is your main income with 65k.
Continue buying Wise cheap for selling and concentrate to get your next Horse. Don't forget to buy additional spare parts and workers. By now, you'll probably won't find fair deals for them, so suck it up and buy even an overpriced one.
Repeat for the last Horse / build your disassembly station in between.