You are lucky at least you have "cyprus" & secondly its free from home. I did this calculation sometimes back and finally opted to buy near the site where the seller was offering free transport, plus a bargain due to quantity.

My conclusion: I would have saved roughly 20-30K which I found not worth due to logistics.
Logistics were shytty and a total nightmare, night travel, offloading, chief letter, 2*2 had alot of wastage, miscalculation (you realize the quantity is not enough after 250KM).
In the end I slept peacefully.

There many ways of killing a rat... some people begin roofing and if it rains midway you buy that black paper and cover the cyprus. If the roofing sheet end midway you still cover with that paper. But its important to plan to the end.

By the way cyprus is strong, it withstands the weather better than the others, it just turns greyish, may loose alignment but holds strong. If you buy chances are high it will be dry & better, if you cut the tree it will be slightly fresh.

If you end up buying, remember the juakali saying "... Have your own tape measure at hand, don't trust the sellers notebook, don't trust the sellers pen & calculator, don't trust the sellers fundi wa mkono preferably go with one, reject edges that are not square (as discount), reconfirm measurements once they arrive at the site. Don't end up with 3 month old saggy pieces, If the seller is a Kisii be alert....."