Diggerman This is the strategy I would offer up to myself if I were starting anew.
CLEARING OUT YOUR CAMP
When clearing slots out of your camp, clear the slots that are 4 spaces high as soon as you are given the opportunity to start clearing from that level. Any piece of Camp Equipment will fit in those 4 high slots, so it is best to have them available should you have the opportunity to get a 4 high piece. That way you won't be in a position of maybe having to pass on that piece or having to struggle to gather the Materials to clear those slots to get that piece in time. Don't limit yourself, though, to only clearing the 4 high slots before you clear any 3 or 2 high slots, but do try to make a sufficient number of 4 high slots available first chance. If you have a few 3 and 2 high pieces in the 4 high slots, then you should clear room in 3 and 2 high grid slots to move them to.
PURCHASING CAMP EQUIPMENT
As far as the Shop items go, you should try to buy the different Carts when you can afford to. Anything 70 per slot and above for regeneration is good for awhile, but you'll soon find that the higher regen and capacity equipment tends to be mostly in the Special Events rather than the Shop, although the Shop will still have some good items so be certain to look through it well to find those as they become available. Also, as you get to the higher Regions you will get some higher value equipment you can purchase, and the newer Special Events being segmented means that equipment for purchase will be more geared towards the Region you happen to be in. That is why that one player's tent was of a higher value than the one you got.
PROFESSOR'S SWITCH SYSTEM
The Professor's Switch System basically allows you to set up two different versions of your camp while being able to use whichever of the same pieces of equipment you choose to place in both camp setups. It is for this reason you should hold onto some of your lower value equipment when you do get the higher value ones, because they might get use acting as filler to give you a little more regeneration or capacity when you get the Professor's Switch System.
Learn the different ones that exist by reading up about them on the Wiki site for Diggy, and try to take as much advantage of them as you can when they arrive.
China is a bear to get through, so it is best to try to get the best equipment you can before getting to it, as well as building up a good deal in food reserves.
DAILY BONUSES AND FREE GIFTS
Make sure to always get your Daily Bonus, and the Diggy fan page and Twitter site give free gifts every so often, so check them out. Also, be sure to check here https://portal.pixelfederation.com/en/gifts