Talk to your trainer and find out if 4K in training is going to get you from unstarted to where you want to be, and then bear in mind that you'll be assuming a lot of risk based on your prospect's potential. I don't know what training board runs in your area or what your trainer charges, but 4K in training won't get you from unstarted to where the prospect you posted about is. (Not a good example, because I don't think this prospect was started or is being ridden correctly or well.)
So I am skeptical of this plan, but if you work out a reasonable plan with your trainer, if you find a very good prospect, and if all the stars line up correctly it might work, so I don't want to be a total buzz kill. It will be difficult to do, but not necessariy impossible.
Good luck, and do keep posting about yoru progress!