If you tell us what you are looking for in a boat and how much you want to pay there will be many helpful members that will suggest various boats listed for sale . Pump out toilet or cassette will generate opinions from both camps but the more details you list the more helpful it will be .
I bought my boat 30 years ago and there was no Forum such as this for advice .
What a pity the surveyor wasn't more specific about where the oil and water leaks were . As has already been pointed out it could cost very little to fix tighten a hose clip and replace a gasket for example . On the other hand worn piston rings , cracked head / block will be an expensive fix.