Go in order of best case scenarios.
Get rid of him and sell him for a decent offer, even 10-15m... dream like
Get rid of him and let him go for free, pretty damn great
Loan him while covering no wages with option to buy, very nice also
Loan him with percentage of wages paid, still very nice
Keep him and have him on the stands, good
Keep him and have in the team as a bench option, this is where it starts to barely work
Keep him and play him... please no
Keep him and start him... god no
Keep him and play him in CL... this is where nightmares start
Keep him and play him in CL in the knockouts... season over.
We are pretty decently with Stegen, one of the top options. Keep him as a tourist. Financially bad, but on the field, it works fine.