Kindergarten again

I've spent the last month thinking about what to do about kindergarten and what is in the best interest for K. He only missed the cutoff by 2 days, and they were willing to admit him early if we got him tested to prove he was ready. I spent at least 2 weeks calling between the doctor, insurance company, school, and multiple school psychologists. The prices were absolutely crazy, and insurance wouldn't cover any of it because it's not a required test. I was getting mixed opinions on whether these people even recommended going through it. Finally I got fed up and stopped for a few days. My mom emailed me one day and said that she found someone who works with her, and they were talking some from the time I started pursuing all this. She was a school psychologist and an early eduction instructor. She was telling my mom that she feels I should consider the testing, and she would be willing to do it for 1/3 the cost of what the other places were telling me. I decided I would call her and she was wonderful. She gave me a ton of info, and before scheduling, she wanted me to talk to his preschool teacher. The only concern about if he could do this, was how is he socially. We know that mentally, he's advanced. Emotionally, he could go and it wouldn't bother him the least that he was gone all day. He would have a blast and not even blink when getting on that bus. (me, I'd be a crazy mess but it isn't exactly about me...)
So anyway, I emailed his preschool teacher a list of questions. She said she would keep an extra close eye on him and make notes and get back to me in about a week. During that time, we started having more behavior issues here. I won't get into it all, other than he is a very strong willed little boy who can be extremely trying at times when he doesn't get exactly what he wants. He is spoiled rotten, and our living arrangement is the big blame to that. We're working on these issues and it's a slow process, but he's slowly getting better. But it made me worry about how he would act in full day school. I don't want him getting a bad start. My brother was ADHD and it was a headache from day 1 for my mother. The school wasn't too supportive and she was constantly getting calls. Kristopher has never been diagnosed with anything, but he's definitely hyper and very strong willed.
So, yesterday was preschool, and after I dropped him off, the teacher pulled me aside and we had our talk. She feels it will be in his best interest to stay home one more year, and just make him as involved as possible in that time frame. She said there is no doubt he would be above ready for the mental and emotional side of things, but for sure, socially he needs work. He has sharing issues, and gets upset when he has to wait his turn for something. Apparently if they have to remind him a few times to wait more patiently, then he gets mad and won't put the same attitude into the project as if he was allowed to go exactly when he wanted. I thought he was different at school because I was never told any of this before. She said it's not really a huge problem, they are able to handle him without much issues, it just takes a little convincing and extra time with him to get him back into things. And she said it's all part of the process of learning to be around his peers.
She said it's pretty common for only children to have issues when they first start these types of things, unless they are started from the beginning. I can't help that he's an only child. That was not my plan. If things worked like we planned, we'd have another close to his age. He would have learned to share from the start of play basically. We live in a pretty isolated area, so there isn't playgroups or neighbors with kids. We have a young amish family on one side and an older couple on the other. And fields all around. He was the only child in my side of the family from up till 3 weeks ago so of course he is used to being the center of attention. My husbands side of the family, there is a lot of other kids, but we don't get along with his siblings at all. The closest would be my SIL and her 3 are terrors and always try to pick at him and he ends up hurt. And they are constantly sick so we avoid them.
Basically, I have to get him majorly socialized in the next year and half. He likes being around others, I just have to make more of an effort to get him more friends. He's got preschool for another week and half. He has T-ball for another month and half. He will play soccer in the fall. And preschool for the fall and spring sessions again. We will do the YMCA swim & gym class in between preschool sessions. I will really have to make a point to go to other areas to get him involved more I guess. I never realized how it was basically hurting him to stay at home with me.....I should have pushed to have him involved sooner.
At least I found it all out now, and didn't push further to get him in and have it be a bad start. And I get one more year to prepare myself for him going all day. We can do one more week long vacation in mid September without having to pull him out of school. And I have over a year before I have to watch him get on a bus and be in someone else's care. I'm sure we are making the right choice now.