shop acquire time

i posted before seeing if anyone could unprotect my map from last year, but i guess noone could do it. so i started over a few days ago, about one fifth done now, most of the terrain and a few triggers here and there have been done, and i found my custom blps in my photoshop folder

i have a question about using shops with my new idea, i have some neutral shops that look like village buildings, when you use the shop, you have to be really close and it takes 10 seconds at least for you to buy from it so it seems like you are searching the house (of course the item will be free since you are raiding the house)

i found where to change the range so you have to be really close, but is there someway i can change the time it takes to use the building?

If you find a way, do post about it, because I don't know.

From my knowledge, if a shop is owned by an opponent, you can't buy items from it. So I am thinking you make a region around the shop and when a hero enters the region, polled wait for 10 seconds, then give it to an ally of the player.