depends o n your experience?
Some crate engines are a bargain,not cheap,just good value.If you buy some kits that you assemble yourself then that is sometimes the answer.
What is it you want? Lets talk about whats the best way to get there.What are the machine shops like in your area and will they help a do it your selfer.Do you know much about finding cheap/free horse power when assembling?What is your budget and purpose of engine? Do you need forged pistons? hundreds of questions,,,,