I'm guessing a chain block would be the safer and than a engine lifter which can be hired from most hire yards, but you need a decent work shop roof beam to sort.

The work shop manual for that motor will give you the lifting point instructions for removal / install and weight..some can be found on the web and downloaded..others you will have to purchase online.

Someone might have a manual and can post a few pics.

I have a 1/2 tonne chain block you can use if required. SOR.

 I had a saltwater 150 on my boat originally and yeah they are heavy. . As Brock said a block and tackle is the go . If you don't have a decent beam in a shed or patio you could try a big limb on a tree if possible. Another option would be to make a heavy duty A frame out of steel as I don't think timber would hold the weight for a period of time. A forklift would be good if you had access to one  

 I took off a 115 2 stroke with an engine lifter, i had to put it on bricks under it to get the right height,  just made up a thingy that screwed into the holes in the flywheel for the lifting point on the engine. i stored it on a steel frame i made up. youll be right just figure it out as you go.

I used a jack under the skeg, lifted it up, then tied it to a rafter to stop it dropping down.

 you can also position  the motor under a beam etc and secure.,  lower trailer on jockey wheel,block of wood under skeg and then raise jockey wheel, undo bolts pull trailer and boat forward or use threaded bar and nuts if all you need to do is get the motor back say  300mm

I’ve removed and replaced many v6 outboards with an engine hoist / crane. Just make sure your on concrete or pavers and must be flat ground. Get the trailer hitch as high as you can using the jockey wheel so the outboard is sitting nice and low

diy outboard engine stand