Hello and thank you! First of all i'm happy to report the situation has already improved a lot! I have read some more on the toddler sleep forum and got right onboard with the suggestion of telling him openly we were leaving and we would come back if needed (instead of trying to get out quietly) and he seems to understand and stay in bed instead of crawling out right away - he even waved goodbye to me today for afternoon nap, so cute!

The last couple of nights only required going back in once and after that he just sat there, whinged quietly a few minutes and then laid down.
It was a normal sized crib with high sides and the bed base set right down - he's quite tall but it sure came as a surprise that he got out that time! Luckily he landed on his bottom but I just wasn't game to see if it would happen again or not...
We used to have a sleeping bag but it's just too hot now and he wasn't sleeping well with it anymore.
So hopefully we are on the right track! Thank you kindly for your response!