That would be great first bike but you may want to negotiate the price a little. It looks to be missing the left side cover and have your mechanic friend check out the fuel valve and/or carbs. It looks to have/had a fuel leak, most likely from the petcock (brown stains around the left foot peg). Neither is a deal breaker, the cover is mostly just cosmetic and the petcock can be repaired or replaced (might just need a gasket or maybe it was just left in the wrong position for extended periods of time). The carbs will likely need to be cleaned.
I'm not telling you all this to scare you away from it, I still think it would be a good first bike. I only mention it so that you might be able to use it a bargaining tool to negotiate a lower price.
Good luck and let us know how it works out!