diff --git a/docs/Func.md b/docs/Func.md
index b207709..db88912 100644
--- a/docs/Func.md
+++ b/docs/Func.md
@@ -17,7 +17,7 @@ The name of the function.
 ### `params`
 Type: `String`<br>
 
-A `String` representation of the body of the function, between parenthesis, including the parenthesis characters. This value will be parsed and the result placed into the `nodes` property.
+A `String` representation of the body of the function, between parenthesis, including the parenthesis characters. This value will be parsed and the result placed into the `nodes` property. This value should be considered only a snapshot for reference. To manipulate function parameters, please leverage the `Container.nodes` property.
 
 ### `type`
 Type: `String`
diff --git a/lib/ValuesStringifier.js b/lib/ValuesStringifier.js
index 8856cf0..06b4c77 100644
--- a/lib/ValuesStringifier.js
+++ b/lib/ValuesStringifier.js
@@ -1,11 +1,13 @@
 const Stringifier = require('postcss/lib/stringifier');
 
 module.exports = class LessStringifier extends Stringifier {
-  basic(node) {
-    const after = this.raw(node, 'after');
+  basic(node, value) {
+    const print = value || node.value;
+    const after = node.raws.after ? this.raw(node, 'after') || '' : '';
+    // NOTE: before is handled by postcss in stringifier.body
 
-    this.builder(node.value, node, 'start');
-    this.builder(after || '', node, 'end');
+    this.builder(print, node, 'start');
+    this.builder(after, node, 'end');
   }
 
   atword(...args) {
@@ -23,25 +25,30 @@ module.exports = class LessStringifier extends Stringifier {
   }
 
   func(node) {
-    const after = this.raw(node, 'after');
+    const after = this.raw(node, 'after') || '';
 
-    this.builder(node.name + node.params, node, 'start');
-    this.builder(after || '', node, 'end');
+    this.builder(`${node.name}(`, node, 'start');
+
+    for (const child of node.nodes) {
+      // since we're duplicating this.body here, we have to handle `before`
+      // but we don't want the postcss default \n value, so check it's non-empty first
+      const before = child.raws.before ? this.raw(child, 'before') : '';
+      if (before) {
+        this.builder(before);
+      }
+      this.stringify(child);
+    }
+
+    this.builder(`)${after}`, node, 'end');
   }
 
   interpolation(node) {
-    const after = this.raw(node, 'after');
-
-    this.builder(node.prefix + node.params, node, 'start');
-    this.builder(after || '', node, 'end');
+    this.basic(node, node.prefix + node.params);
   }
 
   numeric(node) {
-    const start = node.value + node.unit;
-    const after = this.raw(node, 'after');
-
-    this.builder(start, node, 'start');
-    this.builder(after || '', node, 'end');
+    const print = node.value + node.unit;
+    this.basic(node, print);
   }
 
   operator(node) {
diff --git a/lib/index.js b/lib/index.js
index 4c149c1..6f74a68 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -13,8 +13,6 @@ const Input = require('postcss/lib/input');
 const Parser = require('./ValuesParser');
 const Stringifier = require('./ValuesStringifier');
 
-// TODO: walk methods for custom nodes
-
 module.exports = {
   parse(css, options) {
     const input = new Input(css, options);
diff --git a/lib/nodes/Func.js b/lib/nodes/Func.js
index cc7b6c5..945cc87 100644
--- a/lib/nodes/Func.js
+++ b/lib/nodes/Func.js
@@ -84,12 +84,17 @@ class Func extends Container {
       // use a new parser to parse the params of the function. recursion here makes for easier maint
       // we must require this here due to circular dependency resolution
       const { parse } = require('../'); // eslint-disable-line global-require
-      const { nodes: children } = parse(params, opts);
+      const root = parse(params, opts);
+      const { nodes: children } = root;
 
       // TODO: correct line and character position (should we just pad the input? probably easiest)
       for (const child of children) {
         node.push(child);
       }
+
+      if (root.raws.after) {
+        node.last.raws.after = root.raws.after;
+      }
     }
 
     parser.end(lastToken);
diff --git a/test/integration.test.js b/test/integration.test.js
index 5e8bb33..ed9d323 100644
--- a/test/integration.test.js
+++ b/test/integration.test.js
@@ -13,7 +13,8 @@
 */
 const test = require('ava');
 
-const { parse } = require('../lib');
+const { nodeToString, parse } = require('../lib');
+const Punctuation = require('../lib/nodes/Punctuation');
 
 test('integration', (t) => {
   let root = parse(`normal normal 1em/1 'Source Sans Pro', serif`);
@@ -26,3 +27,19 @@ test('integration', (t) => {
   root = parse('1 / -1');
   t.is(root.nodes.length, 3);
 });
+
+test('manipulation', (t) => {
+  const source = 'rgb(100% 100% 100%)';
+  const root = parse(source);
+  const { first } = root;
+
+  let string = nodeToString(root);
+  t.is(source, string);
+
+  first.nodes.splice(1, 0, new Punctuation({ value: ',', parent: first }));
+  first.nodes.splice(3, 0, new Punctuation({ value: ',', parent: first }));
+
+  string = nodeToString(root);
+  t.not(source, string);
+  t.snapshot(string);
+});
diff --git a/test/snapshots/func.test.js.md b/test/snapshots/func.test.js.md
index c10ec09..d0d5c88 100644
--- a/test/snapshots/func.test.js.md
+++ b/test/snapshots/func.test.js.md
@@ -182,7 +182,7 @@ Generated by [AVA](https://ava.li).
           Numeric {
             parent: [Circular],
             raws: {
-              after: '',
+              after: ' ',
               before: ' ',
             },
             source: {
@@ -344,7 +344,7 @@ Generated by [AVA](https://ava.li).
           Numeric {
             parent: [Circular],
             raws: {
-              after: '',
+              after: ' ',
               before: ' ',
             },
             source: {
@@ -1314,7 +1314,7 @@ Generated by [AVA](https://ava.li).
           Numeric {
             parent: [Circular],
             raws: {
-              after: '',
+              after: ' ',
               before: ' ',
             },
             source: {
@@ -1379,7 +1379,7 @@ Generated by [AVA](https://ava.li).
             parent: [Circular],
             quote: '"',
             raws: {
-              after: '',
+              after: ' ',
               before: ' ',
             },
             source: {
@@ -1443,7 +1443,7 @@ Generated by [AVA](https://ava.li).
             parent: [Circular],
             quote: '"',
             raws: {
-              after: '',
+              after: ' ',
               before: ' ',
             },
             source: {
@@ -1507,7 +1507,7 @@ Generated by [AVA](https://ava.li).
             parent: [Circular],
             quote: '\'',
             raws: {
-              after: '',
+              after: ' ',
               before: ' ',
             },
             source: {
@@ -1571,7 +1571,7 @@ Generated by [AVA](https://ava.li).
             parent: [Circular],
             quote: '\'',
             raws: {
-              after: '',
+              after: ' ',
               before: ' ',
             },
             source: {
@@ -1766,7 +1766,7 @@ Generated by [AVA](https://ava.li).
             isVariable: false,
             parent: [Circular],
             raws: {
-              after: '',
+              after: ' ',
               before: '',
             },
             source: {
@@ -1858,7 +1858,7 @@ Generated by [AVA](https://ava.li).
             isVariable: false,
             parent: [Circular],
             raws: {
-              after: '',
+              after: ' ',
               before: ' ',
             },
             source: {
@@ -1950,7 +1950,7 @@ Generated by [AVA](https://ava.li).
             isVariable: false,
             parent: [Circular],
             raws: {
-              after: '',
+              after: ' ',
               before: ' ',
             },
             source: {
diff --git a/test/snapshots/func.test.js.snap b/test/snapshots/func.test.js.snap
index 6deba3e..ba5e040 100644
Binary files a/test/snapshots/func.test.js.snap and b/test/snapshots/func.test.js.snap differ
diff --git a/test/snapshots/integration.test.js.md b/test/snapshots/integration.test.js.md
new file mode 100644
index 0000000..7f822c2
--- /dev/null
+++ b/test/snapshots/integration.test.js.md
@@ -0,0 +1,11 @@
+# Snapshot report for `test/integration.test.js`
+
+The actual snapshot is saved in `integration.test.js.snap`.
+
+Generated by [AVA](https://ava.li).
+
+## manipulation
+
+> Snapshot 1
+
+    'rgb(100%, 100%, 100%)'
diff --git a/test/snapshots/integration.test.js.snap b/test/snapshots/integration.test.js.snap
new file mode 100644
index 0000000..45b9db6
Binary files /dev/null and b/test/snapshots/integration.test.js.snap differ