I am a beginner but I have read the rule book and understood it as best I can. A few queries came up today while I was playing an opponent who may have tried to take advantage IMHO. I say opponent but it was just a standard stroke play game against each other.

Sprinkler Relief
One of my shots landed on a large manhole cover next to the green. This circular manhole was the size of a dustbin lid and sunk about 1/2 foot into the ground. The ball was on the inside against the lip. I said I would take free relief.

Opponent disagreed stating relief was available from sprinkler heads which were much smaller. In his opinion this was not a sprinkler head and he would not allow me relief (he had a smug smile while he said it). Rather than argue I played the shot.

I struck the ball with my SW away from the green and used the lip to rebound it back onto the green with it landing 2 foot from the hole. Opponent called me a lucky **** which while I played for it I probably was

Should i have stood my ground and just taken the free relief?

Temporary Greens
With the same opponent one of my balls landed on the normal green. At a hole with a temporary green. I asked if I should treat the normal green as GUR and take free relief dropping behind it further away from the temp green. My opponent said no as it was not marked as GUR and there was no local ruling posted. I said I was not about to risk taking a divot out of the normal green. I chose a bump and run shoot which IMHO cost me an extra shoot. There was no local ruling about the temporary greens I just thought it would be common sense.

Thoughts?

Hitting Golf Bag
Same opponent a few holes later. The tee is in a hidden spot around the corner of some tees so you tend to leave you golf bag on the path from the last hole to show others you are on the tee. My opponent took his tee shot and hooked it badly. The ball hit his own golf bag. I said that was a penalty but I was unsure if it was one stroke or two. Because I could not quote the rule accurately my opponent said it wasn't and I did not know what I was talking about.

Can anyone clarify the ruling on this for me?

Sprinkler Relief
Sprinkler are usually positioned off the green but maybe be near or on the fringe. This parts of the course is deemed "through the green" and therefore the player is only given free relief if the sprinkler interferes with his stance or swing. If the sprinkler is maerely on the line of play the ball has to be played as it lies. This so call holeman cover is also consider as immovable obstruction just like the sprinkler.

Temporary Greens
I may not undersatnd your question totally but I guess if GUS was not marked or there was no local ruling posted then it is not.

Hitting Golf Bag
If you yourself or your equipment are hit by your ball. 1 penalty strock will be incurred, and the ball has to be played as it lies.

Guru Jay - Please correct me if I am incorrect above.

Query:
Temporary Greens
With the same opponent one of my balls landed on the normal green. At a hole with a temporary green. I asked if I should treat the normal green as GUR and take free relief dropping behind it further away from the temp green. My opponent said no as it was not marked as GUR and there was no local ruling posted. I said I was not about to risk taking a divot out of the normal green. I chose a bump and run shoot which IMHO cost me an extra shoot. There was no local ruling about the temporary greens I just thought it would be common sense.

If the committee assigned a temporary green as the putting green for the hole, the usual green (the normal green) would then be a wrong green, and if your ball lies on a wrong putting green (the normal green) you must not play the ball as it lies. You must take relief, without penalty. Find the NPR and drop within one club-length of the NPR, not nearer the hole. IMO.
Playing from the normal green (wrong green) would be a breach of Rule 25-3 (Match play – Loss of Hole: Stroke play – Two strokes)