Though other DIY Refinishing Kits seem cost efficient they are the opposite. In addition to the $30-$50 Cost you will need a organic compound respirator and other tools to install bring the average cost up to $80. That on top of 4-5 hours to install and clean up. Leaving your house out of service and smelling like chemicals. However, that is not the biggest expense re doing the peeling yellow tub every 6 months- 1 year is. In total over 10 years you are much closer to $1,000 plus your time with rustoleum.
On the other hand for a one time cost of $134.99 Ekopel 2K Will last up to 20 years, provided that there is regular care of the coating. Avoid abrasive cleaners and clean regularly to maintain a long lasting shine.