Consider a Markov chain $X_n$ on $\mathbb{Z}$ with transition probability matrix $S$. Let $C$ be a parameter representing the length of one step. We assume that in each step, we move to a point with distance of order $O(C)$, and the probability of move to each point is of order $C^{-1}$. This makes our Markov chain looks like a random walk. For a random walk, we have the local limit theorem on $P_x(X_n=y)$. So Intuitively, we believe that there should at least be an exponentiallying decaying upper bound for $P_x(X_n=y)$ with respect to $|x-y|/C$ in our setting. But I don't know how to prove this bound, or even the local limit theorem.
I want some references about this kind of estimate or local limit theorem.
Any help is appreciated, thanks in advance.