My only concern with Shankland is the situation with Hearts and Lafferty they obviously had an interest at the end of last season and if Lafferty goes Rangers they might come back for him, personally I think unless Rangers come in for Shankland (and I don't believe they have or will) he's going to be here until the end of the season, he's already got 11 goals so you would expect 20 plus now he's going to a target for clubs in the champ down south or Rangers we all know he's a blue nose so maybe that's what he's hoping for.
The more I think about Hearts, the less worried I am. They think Rangers £200k bid for Lafferty was derisory so let's assume they negotiate them up to £400k and sell. They then approach Ayr for Shankland and the conversation starts something like 'you valued your 30 year old striker in the final year of his deal at £400k, how much more is our 23 year old worth? Oh, and by the way, what about add-ons and a sell-on fee?' I think it's a fairly short conversation.