Welcome to the farm and the forums, Marshin!
It sounds like you are doing well! I'll add my "two coins worth" which will pretty much just confirm the good advice you have already received.
- At level 8 (although you are probably already at a higher level:)) your #1 object should be amassing coins. If you find yourself leveling up and not having sufficient coins to buy the machines and develop the features that arrive at that level, try to do fewer farming activities that give you XP. Avoid double-XP events entirely. The RSS doesn't give you XP. It is the new farmer's friend when it comes to building coins. Check the wikia to see how many coins you will need at the next level.
- It sounds like you are getting good at buying low and selling high!:thumbsup::thumbsup: You've probably already confirmed that everything, including wheat, will sell at max price.
- It's handy to make sure you don't have an ad on anything until you fill all the crates in your shop. Then, when you are ready, you can choose to put an ad on one item. You may choose wheat or eggs if you don't want the hoards descending immediately. Although some of us look for low-level shops because they might have dairy for sale.
- The production slot suggestion is important. Extra slots in the dairy, sugar mill, bakery, and feed mills are worth more to you by far than extra shop crates. I don't think anyone has done a study on the optimal number of shop crates, but I doubt if having more than 10 really pays off.
Happy farming and shopping!
At level 7 best advice is KEEP ALL YOUR MACHINES WORKING ALL THE TIME. You need to evaluate your HD play time frame....how often do you play, every 15 minutes? Every hour? A couple of times a day? Match your crop growth to your time frame and keep growing that crop.....don't grow wheat or corn...too much of that. They don't sell for full price...carrots are good and soy and sugar cane....match crop to your time frame....then keep those fields growing. Make animal feed and sell off your products at full price. Try to find a friend or family who plays as well and is higher level than you...they can usually pass you upgrade items for barn and silo....if so, expand them as much as possible early. I bought the 4000 diamond pack on sale once. I used diamonds to expand all production spots on every machine but DON'T.....I MEAN NEVER....use diamonds to complete crops or production items...use only to expand production slots as you purchase machines. You will never regret that purchase.