Best way as in most $$ or best way as in easiest? The easiest ways yield the least money and the most involved ways yield the most.
Most equals clean it all up, dismantle and part out on eBay. Easiest is sell locally, C/L or FB marketplace. In my market, local sale as is = about 1/4 estimate above. 50/50 chance person buying will then clean it all up and part it out.
Realize repairing will take extra $$ and time. Parting out is actually less work IMO and you don't spend money on parts and consumables.
If you want to sell this bike complete, to maximize $$ the wheels have to match and it needs good tires. Unless you can handle installing tubular tires, this means finding clincher wheels. A nice set of wheels used might cost $100 to $150, even used tires can cost $25 each, tubes, etc. You will never get the $$ in parts and time back in the selling price.
Maximum $$ selling means sell hubs as a set, then stem, bars, seat post, RD, FD, brake calipers as a set, brake levers as a set, bottom bracket, DT shifters as a set, crankset, pedals. and finally frame/fork/headest. Thats 12 auctions, maybe 13 if you try to sell saddle. Could be $1200 total, could be more. Chances of selling whole for $1200? ZERO.
Last edited by wrk101; 02-13-22 at 12:25 AM.