Don't buy something that fits the budget now with the intention of trading up in a couple of years. It takes a couple of annuals for you, and your maintenance provider, to get "in tune" with the aircraft and bring it (and the paperwork) up to a condition that you both like. These are the expensive years..........don't fettle something and then sell it; you won't get your money back.
When you do buy - take somebody with authority from your chosen maintenance provider to do the pre-purchase inspection. It won't be cheap but you then have leverage when they "discover" something nasty at the first annual.